diff --git a/logs/file.go b/logs/file.go
index b87664bd..f75e5bae 100644
--- a/logs/file.go
+++ b/logs/file.go
@@ -22,6 +22,7 @@ import (
 	"io"
 	"os"
 	"path/filepath"
+	"strconv"
 	"strings"
 	"sync"
 	"time"
@@ -53,7 +54,8 @@ type fileLogWriter struct {
 
 	Level int `json:"level"`
 
-	Perm os.FileMode `json:"perm"`
+	Perm string `json:"perm"`
+	perm os.FileMode
 
 	fileNameOnly, suffix string // like "project.log", project is fileNameOnly and .log is suffix
 }
@@ -65,7 +67,8 @@ func newFileWriter() Logger {
 		MaxDays: 7,
 		Rotate:  true,
 		Level:   LevelTrace,
-		Perm:    0660,
+		Perm:    "0660",
+		perm:    0660,
 	}
 	return w
 }
@@ -89,6 +92,11 @@ func (w *fileLogWriter) Init(jsonConfig string) error {
 	if len(w.Filename) == 0 {
 		return errors.New("jsonconfig must have filename")
 	}
+	perm, err := strconv.ParseInt(w.Perm, 8, 64)
+	if err != nil {
+		return err
+	}
+	w.perm = os.FileMode(perm)
 	w.suffix = filepath.Ext(w.Filename)
 	w.fileNameOnly = strings.TrimSuffix(w.Filename, w.suffix)
 	if w.suffix == "" {
@@ -153,7 +161,7 @@ func (w *fileLogWriter) WriteMsg(when time.Time, msg string, level int) error {
 
 func (w *fileLogWriter) createLogFile() (*os.File, error) {
 	// Open the log file
-	fd, err := os.OpenFile(w.Filename, os.O_WRONLY|os.O_APPEND|os.O_CREATE, w.Perm)
+	fd, err := os.OpenFile(w.Filename, os.O_WRONLY|os.O_APPEND|os.O_CREATE, w.perm)
 	return fd, err
 }
 
diff --git a/logs/file_test.go b/logs/file_test.go
index d468606c..23370947 100644
--- a/logs/file_test.go
+++ b/logs/file_test.go
@@ -24,6 +24,27 @@ import (
 	"time"
 )
 
+func TestFilePerm(t *testing.T) {
+	log := NewLogger(10000)
+	log.SetLogger("file", `{"filename":"test.log", "perm": "0600"}`)
+	log.Debug("debug")
+	log.Informational("info")
+	log.Notice("notice")
+	log.Warning("warning")
+	log.Error("error")
+	log.Alert("alert")
+	log.Critical("critical")
+	log.Emergency("emergency")
+	file, err := os.Stat("test.log")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if file.Mode() != 0600 {
+		t.Fatal("unexpected log file permission")
+	}
+	os.Remove("test.log")
+}
+
 func TestFile1(t *testing.T) {
 	log := NewLogger(10000)
 	log.SetLogger("file", `{"filename":"test.log"}`)
@@ -147,7 +168,7 @@ func testFileRotate(t *testing.T, fn1, fn2 string) {
 		MaxDays: 7,
 		Rotate:  true,
 		Level:   LevelTrace,
-		Perm:    0660,
+		Perm:    "0660",
 	}
 	fw.Init(fmt.Sprintf(`{"filename":"%v","maxdays":1}`, fn1))
 	fw.dailyOpenTime = time.Now().Add(-24 * time.Hour)
@@ -170,7 +191,7 @@ func testFileDailyRotate(t *testing.T, fn1, fn2 string) {
 		MaxDays: 7,
 		Rotate:  true,
 		Level:   LevelTrace,
-		Perm:    0660,
+		Perm:    "0660",
 	}
 	fw.Init(fmt.Sprintf(`{"filename":"%v","maxdays":1}`, fn1))
 	fw.dailyOpenTime = time.Now().Add(-24 * time.Hour)