diff --git a/command/config_test.go b/command/config_test.go
index 61f89ddf8..53654f54f 100644
--- a/command/config_test.go
+++ b/command/config_test.go
@@ -49,23 +49,31 @@ func TestConfigGet_not_found(t *testing.T) {
 func TestConfigSet(t *testing.T) {
 	initBlankContext("", "OWNER/REPO", "master")
 
-	buf := bytes.NewBufferString("")
-	defer config.StubWriteConfig(buf, nil)()
+	mainBuf := bytes.Buffer{}
+	hostsBuf := bytes.Buffer{}
+	defer config.StubWriteConfig(&mainBuf, &hostsBuf)()
+
 	output, err := RunCommand("config set editor ed")
 	if err != nil {
 		t.Fatalf("error running command `config set editor ed`: %v", err)
 	}
 
-	eq(t, output.String(), "")
+	if len(output.String()) > 0 {
+		t.Errorf("expected output to be blank: %q", output.String())
+	}
 
-	expected := `hosts:
-    github.com:
-        user: OWNER
-        oauth_token: 1234567890
-editor: ed
+	expectedMain := "editor: ed\n"
+	expectedHosts := `github.com:
+    user: OWNER
+    oauth_token: "1234567890"
 `
 
-	eq(t, buf.String(), expected)
+	if mainBuf.String() != expectedMain {
+		t.Errorf("expected config.yml to be %q, got %q", expectedMain, mainBuf.String())
+	}
+	if hostsBuf.String() != expectedHosts {
+		t.Errorf("expected hosts.yml to be %q, got %q", expectedHosts, hostsBuf.String())
+	}
 }
 
 func TestConfigSet_update(t *testing.T) {
@@ -79,23 +87,31 @@ editor: ed
 
 	initBlankContext(cfg, "OWNER/REPO", "master")
 
-	buf := bytes.NewBufferString("")
-	defer config.StubWriteConfig(buf, nil)()
+	mainBuf := bytes.Buffer{}
+	hostsBuf := bytes.Buffer{}
+	defer config.StubWriteConfig(&mainBuf, &hostsBuf)()
 
 	output, err := RunCommand("config set editor vim")
 	if err != nil {
 		t.Fatalf("error running command `config get editor`: %v", err)
 	}
 
-	eq(t, output.String(), "")
+	if len(output.String()) > 0 {
+		t.Errorf("expected output to be blank: %q", output.String())
+	}
 
-	expected := `hosts:
-    github.com:
-        user: OWNER
-        oauth_token: MUSTBEHIGHCUZIMATOKEN
-editor: vim
+	expectedMain := "editor: vim\n"
+	expectedHosts := `github.com:
+    user: OWNER
+    oauth_token: MUSTBEHIGHCUZIMATOKEN
 `
-	eq(t, buf.String(), expected)
+
+	if mainBuf.String() != expectedMain {
+		t.Errorf("expected config.yml to be %q, got %q", expectedMain, mainBuf.String())
+	}
+	if hostsBuf.String() != expectedHosts {
+		t.Errorf("expected hosts.yml to be %q, got %q", expectedHosts, hostsBuf.String())
+	}
 }
 
 func TestConfigGetHost(t *testing.T) {
@@ -141,23 +157,32 @@ git_protocol: ssh
 func TestConfigSetHost(t *testing.T) {
 	initBlankContext("", "OWNER/REPO", "master")
 
-	buf := bytes.NewBufferString("")
-	defer config.StubWriteConfig(buf, nil)()
+	mainBuf := bytes.Buffer{}
+	hostsBuf := bytes.Buffer{}
+	defer config.StubWriteConfig(&mainBuf, &hostsBuf)()
+
 	output, err := RunCommand("config set -hgithub.com git_protocol ssh")
 	if err != nil {
 		t.Fatalf("error running command `config set editor ed`: %v", err)
 	}
 
-	eq(t, output.String(), "")
+	if len(output.String()) > 0 {
+		t.Errorf("expected output to be blank: %q", output.String())
+	}
 
-	expected := `hosts:
-    github.com:
-        user: OWNER
-        oauth_token: 1234567890
-        git_protocol: ssh
+	expectedMain := ""
+	expectedHosts := `github.com:
+    user: OWNER
+    oauth_token: "1234567890"
+    git_protocol: ssh
 `
 
-	eq(t, buf.String(), expected)
+	if mainBuf.String() != expectedMain {
+		t.Errorf("expected config.yml to be %q, got %q", expectedMain, mainBuf.String())
+	}
+	if hostsBuf.String() != expectedHosts {
+		t.Errorf("expected hosts.yml to be %q, got %q", expectedHosts, hostsBuf.String())
+	}
 }
 
 func TestConfigSetHost_update(t *testing.T) {
@@ -171,21 +196,30 @@ hosts:
 
 	initBlankContext(cfg, "OWNER/REPO", "master")
 
-	buf := bytes.NewBufferString("")
-	defer config.StubWriteConfig(buf, nil)()
+	mainBuf := bytes.Buffer{}
+	hostsBuf := bytes.Buffer{}
+	defer config.StubWriteConfig(&mainBuf, &hostsBuf)()
 
 	output, err := RunCommand("config set -hgithub.com git_protocol https")
 	if err != nil {
 		t.Fatalf("error running command `config get editor`: %v", err)
 	}
 
-	eq(t, output.String(), "")
+	if len(output.String()) > 0 {
+		t.Errorf("expected output to be blank: %q", output.String())
+	}
 
-	expected := `hosts:
-    github.com:
-        git_protocol: https
-        user: OWNER
-        oauth_token: MUSTBEHIGHCUZIMATOKEN
+	expectedMain := ""
+	expectedHosts := `github.com:
+    git_protocol: https
+    user: OWNER
+    oauth_token: MUSTBEHIGHCUZIMATOKEN
 `
-	eq(t, buf.String(), expected)
+
+	if mainBuf.String() != expectedMain {
+		t.Errorf("expected config.yml to be %q, got %q", expectedMain, mainBuf.String())
+	}
+	if hostsBuf.String() != expectedHosts {
+		t.Errorf("expected hosts.yml to be %q, got %q", expectedHosts, hostsBuf.String())
+	}
 }
diff --git a/command/testing.go b/command/testing.go
index 2ca2ad19e..af713aa29 100644
--- a/command/testing.go
+++ b/command/testing.go
@@ -19,7 +19,7 @@ import (
 const defaultTestConfig = `hosts:
   github.com:
     user: OWNER
-    oauth_token: 1234567890
+    oauth_token: "1234567890"
 `
 
 type askStubber struct {
diff --git a/internal/config/config_file.go b/internal/config/config_file.go
index ff10d446f..71fffb0d1 100644
--- a/internal/config/config_file.go
+++ b/internal/config/config_file.go
@@ -7,7 +7,6 @@ import (
 	"io/ioutil"
 	"os"
 	"path"
-	"path/filepath"
 
 	"github.com/mitchellh/go-homedir"
 	"gopkg.in/yaml.v3"
@@ -22,6 +21,10 @@ func ConfigFile() string {
 	return path.Join(ConfigDir(), "config.yml")
 }
 
+func hostsConfigFile(fn string) string {
+	return path.Join(path.Dir(fn), "hosts.yml")
+}
+
 func ParseDefaultConfig() (Config, error) {
 	return ParseConfig(ConfigFile())
 }
@@ -42,7 +45,7 @@ var ReadConfigFile = func(fn string) ([]byte, error) {
 }
 
 var WriteConfigFile = func(fn string, data []byte) error {
-	err := os.MkdirAll(filepath.Dir(fn), 0771)
+	err := os.MkdirAll(path.Dir(fn), 0771)
 	if err != nil {
 		return err
 	}
@@ -91,73 +94,44 @@ func parseConfigFile(fn string) ([]byte, *yaml.Node, error) {
 
 func isLegacy(root *yaml.Node) bool {
 	for _, v := range root.Content[0].Content {
-		if v.Value == "hosts" {
-			return false
+		if v.Value == "github.com" {
+			return true
 		}
 	}
 
-	return true
+	return false
 }
 
-func migrateConfig(fn string, root *yaml.Node) error {
-	type ConfigEntry map[string]string
-	type ConfigHash map[string]ConfigEntry
-
-	newConfigData := map[string]ConfigHash{}
-	newConfigData["hosts"] = ConfigHash{}
-
-	topLevelKeys := root.Content[0].Content
-
-	for i, x := range topLevelKeys {
-		if x.Value == "" {
-			continue
-		}
-		if i+1 == len(topLevelKeys) {
-			break
-		}
-		hostname := x.Value
-		newConfigData["hosts"][hostname] = ConfigEntry{}
-
-		authKeys := topLevelKeys[i+1].Content[0].Content
-
-		for j, y := range authKeys {
-			if j+1 == len(authKeys) {
-				break
-			}
-			switch y.Value {
-			case "user":
-				newConfigData["hosts"][hostname]["user"] = authKeys[j+1].Value
-			case "oauth_token":
-				newConfigData["hosts"][hostname]["oauth_token"] = authKeys[j+1].Value
-			}
-		}
-	}
-
-	if _, ok := newConfigData["hosts"][defaultHostname]; !ok {
-		return errors.New("could not find default host configuration")
-	}
-
-	defaultHostConfig := newConfigData["hosts"][defaultHostname]
-
-	if _, ok := defaultHostConfig["user"]; !ok {
-		return errors.New("default host configuration missing user")
-	}
-
-	if _, ok := defaultHostConfig["oauth_token"]; !ok {
-		return errors.New("default host configuration missing oauth_token")
-	}
-
-	newConfig, err := yaml.Marshal(newConfigData)
+func migrateConfig(fn string) error {
+	b, err := ReadConfigFile(fn)
 	if err != nil {
 		return err
 	}
 
+	var hosts map[string][]map[string]string
+	err = yaml.Unmarshal(b, &hosts)
+	if err != nil {
+		return fmt.Errorf("error decoding legacy format: %w", err)
+	}
+
+	cfg := NewBlankConfig()
+	for hostname, entries := range hosts {
+		if len(entries) < 1 {
+			continue
+		}
+		for key, value := range entries[0] {
+			if err := cfg.Set(hostname, key, value); err != nil {
+				return err
+			}
+		}
+	}
+
 	err = BackupConfigFile(fn)
 	if err != nil {
 		return fmt.Errorf("failed to back up existing config: %w", err)
 	}
 
-	return WriteConfigFile(fn, newConfig)
+	return cfg.Write()
 }
 
 func ParseConfig(fn string) (Config, error) {
@@ -167,15 +141,28 @@ func ParseConfig(fn string) (Config, error) {
 	}
 
 	if isLegacy(root) {
-		err = migrateConfig(fn, root)
+		err = migrateConfig(fn)
 		if err != nil {
-			return nil, err
+			return nil, fmt.Errorf("error migrating legacy config: %w", err)
 		}
 
 		_, root, err = parseConfigFile(fn)
 		if err != nil {
 			return nil, fmt.Errorf("failed to reparse migrated config: %w", err)
 		}
+	} else {
+		if _, hostsRoot, err := parseConfigFile(hostsConfigFile(fn)); err == nil {
+			if len(hostsRoot.Content[0].Content) > 0 {
+				newContent := []*yaml.Node{
+					{Value: "hosts"},
+					hostsRoot.Content[0],
+				}
+				restContent := root.Content[0].Content
+				root.Content[0].Content = append(newContent, restContent...)
+			}
+		} else if !errors.Is(err, os.ErrNotExist) {
+			return nil, err
+		}
 	}
 
 	return NewConfig(root), nil
diff --git a/internal/config/config_file_test.go b/internal/config/config_file_test.go
index 441dc22f2..edc3a6ae9 100644
--- a/internal/config/config_file_test.go
+++ b/internal/config/config_file_test.go
@@ -54,6 +54,22 @@ hosts:
 	eq(t, token, "OTOKEN")
 }
 
+func Test_parseConfig_hostsFile(t *testing.T) {
+	defer StubConfig("", `---
+github.com:
+  user: monalisa
+  oauth_token: OTOKEN
+`)()
+	config, err := ParseConfig("config.yml")
+	eq(t, err, nil)
+	user, err := config.Get("github.com", "user")
+	eq(t, err, nil)
+	eq(t, user, "monalisa")
+	token, err := config.Get("github.com", "oauth_token")
+	eq(t, err, nil)
+	eq(t, token, "OTOKEN")
+}
+
 func Test_parseConfig_notFound(t *testing.T) {
 	defer StubConfig(`---
 hosts:
@@ -67,33 +83,29 @@ hosts:
 	eq(t, err, &NotFoundError{errors.New(`could not find config entry for "github.com"`)})
 }
 
-func Test_migrateConfig(t *testing.T) {
-	oldStyle := `---
+func Test_ParseConfig_migrateConfig(t *testing.T) {
+	defer StubConfig(`---
 github.com:
   - user: keiyuri
-    oauth_token: 123456`
-
-	var root yaml.Node
-	err := yaml.Unmarshal([]byte(oldStyle), &root)
-	if err != nil {
-		panic("failed to parse test yaml")
-	}
-
-	buf := bytes.NewBufferString("")
-	defer StubWriteConfig(buf, nil)()
+    oauth_token: 123456
+`, "")()
 
+	mainBuf := bytes.Buffer{}
+	hostsBuf := bytes.Buffer{}
+	defer StubWriteConfig(&mainBuf, &hostsBuf)()
 	defer StubBackupConfig()()
 
-	err = migrateConfig("config.yml", &root)
+	_, err := ParseConfig("config.yml")
 	eq(t, err, nil)
 
-	expected := `hosts:
-    github.com:
-        oauth_token: "123456"
-        user: keiyuri
+	expectedMain := ""
+	expectedHosts := `github.com:
+    user: keiyuri
+    oauth_token: "123456"
 `
 
-	eq(t, buf.String(), expected)
+	eq(t, mainBuf.String(), expectedMain)
+	eq(t, hostsBuf.String(), expectedHosts)
 }
 
 func Test_parseConfigFile(t *testing.T) {
diff --git a/internal/config/config_type.go b/internal/config/config_type.go
index c2fc66d9b..f965b2c66 100644
--- a/internal/config/config_type.go
+++ b/internal/config/config_type.go
@@ -54,6 +54,7 @@ func (cm *ConfigMap) SetStringValue(key, value string) error {
 		}
 		valueNode = &yaml.Node{
 			Kind:  yaml.ScalarNode,
+			Tag:   "!!str",
 			Value: "",
 		}
 
@@ -168,16 +169,42 @@ func (c *fileConfig) configForHost(hostname string) (*HostConfig, error) {
 }
 
 func (c *fileConfig) Write() error {
-	marshalled, err := yaml.Marshal(c.documentRoot)
+	mainData := yaml.Node{Kind: yaml.MappingNode}
+	hostsData := yaml.Node{Kind: yaml.MappingNode}
+
+	nodes := c.documentRoot.Content[0].Content
+	for i := 0; i < len(nodes)-1; i += 2 {
+		if nodes[i].Value == "hosts" {
+			hostsData.Content = append(hostsData.Content, nodes[i+1].Content...)
+		} else {
+			mainData.Content = append(mainData.Content, nodes[i], nodes[i+1])
+		}
+	}
+
+	mainBytes, err := yaml.Marshal(&mainData)
 	if err != nil {
 		return err
 	}
 
-	if bytes.Equal(marshalled, []byte("{}\n")) {
-		marshalled = []byte{}
+	fn := ConfigFile()
+	err = WriteConfigFile(fn, yamlNormalize(mainBytes))
+	if err != nil {
+		return err
 	}
 
-	return WriteConfigFile(ConfigFile(), marshalled)
+	hostsBytes, err := yaml.Marshal(&hostsData)
+	if err != nil {
+		return err
+	}
+
+	return WriteConfigFile(hostsConfigFile(fn), yamlNormalize(hostsBytes))
+}
+
+func yamlNormalize(b []byte) []byte {
+	if bytes.Equal(b, []byte("{}\n")) {
+		return []byte{}
+	}
+	return b
 }
 
 func (c *fileConfig) hostEntries() ([]*HostConfig, error) {
diff --git a/internal/config/config_type_test.go b/internal/config/config_type_test.go
index 97ffd9aa7..1c8105186 100644
--- a/internal/config/config_type_test.go
+++ b/internal/config/config_type_test.go
@@ -8,8 +8,9 @@ import (
 )
 
 func Test_fileConfig_Set(t *testing.T) {
-	cb := bytes.Buffer{}
-	StubWriteConfig(&cb, nil)
+	mainBuf := bytes.Buffer{}
+	hostsBuf := bytes.Buffer{}
+	defer StubWriteConfig(&mainBuf, &hostsBuf)()
 
 	c := NewBlankConfig()
 	assert.NoError(t, c.Set("", "editor", "nano"))
@@ -18,22 +19,23 @@ func Test_fileConfig_Set(t *testing.T) {
 	assert.NoError(t, c.Set("github.com", "user", "hubot"))
 	assert.NoError(t, c.Write())
 
-	assert.Equal(t, `editor: nano
-hosts:
-    github.com:
-        git_protocol: ssh
-        user: hubot
-    example.com:
-        editor: vim
-`, cb.String())
+	assert.Equal(t, "editor: nano\n", mainBuf.String())
+	assert.Equal(t, `github.com:
+    git_protocol: ssh
+    user: hubot
+example.com:
+    editor: vim
+`, hostsBuf.String())
 }
 
 func Test_fileConfig_Write(t *testing.T) {
-	cb := bytes.Buffer{}
-	StubWriteConfig(&cb, nil)
+	mainBuf := bytes.Buffer{}
+	hostsBuf := bytes.Buffer{}
+	defer StubWriteConfig(&mainBuf, &hostsBuf)()
 
 	c := NewBlankConfig()
 	assert.NoError(t, c.Write())
 
-	assert.Equal(t, "", cb.String())
+	assert.Equal(t, "", mainBuf.String())
+	assert.Equal(t, "", hostsBuf.String())
 }