diff --git a/pkg/channels/irc/irc.go b/pkg/channels/irc/irc.go
index 28c59b540..2f8458f3a 100644
--- a/pkg/channels/irc/irc.go
+++ b/pkg/channels/irc/irc.go
@@ -32,6 +32,7 @@ func NewIRCChannel(cfg config.IRCConfig, messageBus *bus.MessageBus) (*IRCChanne
 	if cfg.Nick == "" {
 		return nil, fmt.Errorf("irc nick is required")
 	}
+	cfg.Channels = normalizeIRCChannels(cfg.Channels)
 
 	base := channels.NewBaseChannel("irc", cfg, messageBus, cfg.AllowFrom,
 		channels.WithMaxMessageLength(400),
@@ -192,3 +193,24 @@ func extractHost(server string) string {
 	}
 	return server
 }
+
+func normalizeIRCChannels(channels config.FlexibleStringSlice) config.FlexibleStringSlice {
+	if len(channels) == 0 {
+		return channels
+	}
+
+	normalized := make(config.FlexibleStringSlice, 0, len(channels))
+	for _, channel := range channels {
+		channel = strings.TrimSpace(channel)
+		if channel == "" {
+			continue
+		}
+		switch channel[0] {
+		case '#', '&', '+', '!':
+			normalized = append(normalized, channel)
+		default:
+			normalized = append(normalized, "#"+channel)
+		}
+	}
+	return normalized
+}
diff --git a/pkg/channels/irc/irc_test.go b/pkg/channels/irc/irc_test.go
index 168252a4d..9ac3042c3 100644
--- a/pkg/channels/irc/irc_test.go
+++ b/pkg/channels/irc/irc_test.go
@@ -1,6 +1,7 @@
 package irc
 
 import (
+	"reflect"
 	"testing"
 
 	"github.com/sipeed/picoclaw/pkg/bus"
@@ -43,6 +44,23 @@ func TestNewIRCChannel(t *testing.T) {
 			t.Error("new channel should not be running")
 		}
 	})
+
+	t.Run("normalizes auto join channels", func(t *testing.T) {
+		cfg := config.IRCConfig{
+			Server:   "irc.example.com:6667",
+			Nick:     "testbot",
+			Channels: []string{" general ", "#already", "&ops", "+local", "!safe", "", "news"},
+		}
+		ch, err := NewIRCChannel(cfg, msgBus)
+		if err != nil {
+			t.Fatalf("unexpected error: %v", err)
+		}
+
+		want := config.FlexibleStringSlice{"#general", "#already", "&ops", "+local", "!safe", "#news"}
+		if !reflect.DeepEqual(ch.config.Channels, want) {
+			t.Fatalf("Channels = %#v, want %#v", ch.config.Channels, want)
+		}
+	})
 }
 
 func TestExtractHost(t *testing.T) {
diff --git a/pkg/config/config.go b/pkg/config/config.go
index 7a7edb489..08e89864a 100644
--- a/pkg/config/config.go
+++ b/pkg/config/config.go
@@ -29,6 +29,13 @@ func (f *FlexibleStringSlice) UnmarshalJSON(data []byte) error {
 		return nil
 	}
 
+	// Accept a single string so config patch APIs can submit comma-separated values.
+	var s string
+	if err := json.Unmarshal(data, &s); err == nil {
+		*f = parseFlexibleStringSlice(s)
+		return nil
+	}
+
 	// Try []interface{} to handle mixed types
 	var raw []any
 	if err := json.Unmarshal(data, &raw); err != nil {
@@ -57,21 +64,22 @@ func (f *FlexibleStringSlice) UnmarshalText(text []byte) error {
 		*f = nil
 		return nil
 	}
+	*f = parseFlexibleStringSlice(string(text))
+	return nil
+}
 
-	s := string(text)
-	// Replace Chinese comma with English comma, then split
+func parseFlexibleStringSlice(s string) FlexibleStringSlice {
 	s = strings.ReplaceAll(s, "，", ",")
 	parts := strings.Split(s, ",")
 
-	result := make([]string, 0, len(parts))
+	result := make(FlexibleStringSlice, 0, len(parts))
 	for _, part := range parts {
 		part = strings.TrimSpace(part)
 		if part != "" {
 			result = append(result, part)
 		}
 	}
-	*f = result
-	return nil
+	return result
 }
 
 type Config struct {
diff --git a/pkg/config/flexible_string_slice_test.go b/pkg/config/flexible_string_slice_test.go
new file mode 100644
index 000000000..a5bb1763d
--- /dev/null
+++ b/pkg/config/flexible_string_slice_test.go
@@ -0,0 +1,19 @@
+package config
+
+import (
+	"encoding/json"
+	"reflect"
+	"testing"
+)
+
+func TestFlexibleStringSliceUnmarshalJSON_String(t *testing.T) {
+	var got FlexibleStringSlice
+	if err := json.Unmarshal([]byte(`"general, #ops，dev"`), &got); err != nil {
+		t.Fatalf("Unmarshal() error = %v", err)
+	}
+
+	want := FlexibleStringSlice{"general", "#ops", "dev"}
+	if !reflect.DeepEqual(got, want) {
+		t.Fatalf("FlexibleStringSlice = %#v, want %#v", got, want)
+	}
+}
diff --git a/web/backend/api/config_test.go b/web/backend/api/config_test.go
index 29811e37e..1daa4a835 100644
--- a/web/backend/api/config_test.go
+++ b/web/backend/api/config_test.go
@@ -4,6 +4,7 @@ import (
 	"bytes"
 	"net/http"
 	"net/http/httptest"
+	"reflect"
 	"testing"
 
 	"github.com/sipeed/picoclaw/pkg/config"
@@ -86,3 +87,40 @@ func TestHandleUpdateConfig_DoesNotInheritDefaultModelFields(t *testing.T) {
 		t.Fatalf("model_list[0].api_base = %q, want empty string", got)
 	}
 }
+
+func TestHandlePatchConfig_AcceptsFlexibleStringSliceString(t *testing.T) {
+	configPath, cleanup := setupOAuthTestEnv(t)
+	defer cleanup()
+
+	h := NewHandler(configPath)
+	mux := http.NewServeMux()
+	h.RegisterRoutes(mux)
+
+	req := httptest.NewRequest(http.MethodPatch, "/api/config", bytes.NewBufferString(`{
+		"channels": {
+			"irc": {
+				"enabled": true,
+				"server": "irc.example.com:6667",
+				"nick": "testbot",
+				"channels": "general, #ops，dev"
+			}
+		}
+	}`))
+	req.Header.Set("Content-Type", "application/json")
+
+	rec := httptest.NewRecorder()
+	mux.ServeHTTP(rec, req)
+	if rec.Code != http.StatusOK {
+		t.Fatalf("status = %d, want %d, body=%s", rec.Code, http.StatusOK, rec.Body.String())
+	}
+
+	cfg, err := config.LoadConfig(configPath)
+	if err != nil {
+		t.Fatalf("LoadConfig() error = %v", err)
+	}
+
+	want := config.FlexibleStringSlice{"general", "#ops", "dev"}
+	if !reflect.DeepEqual(cfg.Channels.IRC.Channels, want) {
+		t.Fatalf("channels.irc.channels = %#v, want %#v", cfg.Channels.IRC.Channels, want)
+	}
+}