diff --git a/component/geodata/utils.go b/component/geodata/utils.go
index 1cf7c63c..e919ce56 100644
--- a/component/geodata/utils.go
+++ b/component/geodata/utils.go
@@ -2,6 +2,7 @@ package geodata
 
 import (
 	"github.com/Dreamacro/clash/component/geodata/router"
+	C "github.com/Dreamacro/clash/constant"
 	"strings"
 )
 
@@ -17,6 +18,19 @@ func SetLoader(newLoader string) {
 	geoLoaderName = newLoader
 }
 
+func Verify(name string) bool {
+	switch name {
+	case C.GeositeName:
+		_, _, err := LoadGeoSiteMatcher("CN")
+		return err == nil
+	case C.GeoipName:
+		_, _, err := LoadGeoIPMatcher("CN")
+		return err == nil
+	default:
+		return false
+	}
+}
+
 func LoadGeoSiteMatcher(countryCode string) (*router.DomainMatcher, int, error) {
 	geoLoader, err := GetGeoDataLoader(geoLoaderName)
 	if err != nil {
diff --git a/config/config.go b/config/config.go
index 8d9465ec..9cc0b3bf 100644
--- a/config/config.go
+++ b/config/config.go
@@ -41,6 +41,7 @@ type General struct {
 	LogLevel      log.LogLevel `json:"log-level"`
 	IPv6          bool         `json:"ipv6"`
 	Interface     string       `json:"-"`
+	GeodataMode   string       `json:"geodata-mode"`
 	GeodataLoader string       `json:"geodata-loader"`
 	AutoIptables  bool         `json:"auto-iptables"`
 }
@@ -172,6 +173,7 @@ type RawConfig struct {
 	ExternalUI         string       `yaml:"external-ui"`
 	Secret             string       `yaml:"secret"`
 	Interface          string       `yaml:"interface-name"`
+	GeodataMode        string       `yaml:"geodata-mode"`
 	GeodataLoader      string       `yaml:"geodata-loader"`
 	AutoIptables       bool         `yaml:"auto-iptables"`
 
@@ -204,6 +206,7 @@ func UnmarshalRawConfig(buf []byte) (*RawConfig, error) {
 		AllowLan:       false,
 		BindAddress:    "*",
 		Mode:           T.Rule,
+		GeodataMode:    "dat",
 		GeodataLoader:  "memconservative",
 		AutoIptables:   false,
 		UnifiedDelay:   false,
diff --git a/config/initial.go b/config/initial.go
index b2acaa2a..d3c2ce35 100644
--- a/config/initial.go
+++ b/config/initial.go
@@ -2,6 +2,7 @@ package config
 
 import (
 	"fmt"
+	"github.com/Dreamacro/clash/component/geodata"
 	"github.com/Dreamacro/clash/component/mmdb"
 	"io"
 	"net/http"
@@ -11,6 +12,8 @@ import (
 	"github.com/Dreamacro/clash/log"
 )
 
+var GeodataMode bool
+
 func downloadMMDB(path string) (err error) {
 	resp, err := http.Get("https://cdn.jsdelivr.net/gh/Loyalsoldier/geoip@release/Country.mmdb")
 	if err != nil {
@@ -71,16 +74,38 @@ func initGeoSite() error {
 		log.Infoln("Download GeoSite.dat finish")
 	}
 
+	if !geodata.Verify(C.GeositeName) {
+		log.Warnln("GeoSite.dat invalid, remove and download")
+		if err := os.Remove(C.Path.GeoSite()); err != nil {
+			return fmt.Errorf("can't remove invalid GeoSite.dat: %s", err.Error())
+		}
+		if err := downloadGeoSite(C.Path.GeoSite()); err != nil {
+			return fmt.Errorf("can't download GeoSite.dat: %s", err.Error())
+		}
+	}
 	return nil
 }
 
 func initGeoIP() error {
-	if _, err := os.Stat(C.Path.GeoIP()); os.IsNotExist(err) {
-		log.Infoln("Need GeoIP but can't find GeoIP.dat, start download")
-		if err := downloadGeoIP(C.Path.GeoIP()); err != nil {
-			return fmt.Errorf("can't download GeoIP.dat: %s", err.Error())
+	if GeodataMode {
+		if _, err := os.Stat(C.Path.GeoIP()); os.IsNotExist(err) {
+			log.Infoln("Need GeoIP but can't find GeoIP.dat, start download")
+			if err := downloadGeoIP(C.Path.GeoIP()); err != nil {
+				return fmt.Errorf("can't download GeoIP.dat: %s", err.Error())
+			}
+			log.Infoln("Download GeoIP.dat finish")
 		}
-		log.Infoln("Download GeoIP.dat finish")
+
+		if !geodata.Verify(C.GeoipName) {
+			log.Warnln("GeoIP.dat invalid, remove and download")
+			if err := os.Remove(C.Path.GeoIP()); err != nil {
+				return fmt.Errorf("can't remove invalid GeoIP.dat: %s", err.Error())
+			}
+			if err := downloadGeoIP(C.Path.GeoIP()); err != nil {
+				return fmt.Errorf("can't download GeoIP.dat: %s", err.Error())
+			}
+		}
+		return nil
 	}
 
 	if _, err := os.Stat(C.Path.MMDB()); os.IsNotExist(err) {
diff --git a/main.go b/main.go
index 8d9daff7..cd98a89b 100644
--- a/main.go
+++ b/main.go
@@ -22,6 +22,7 @@ var (
 	flagset            map[string]bool
 	version            bool
 	testConfig         bool
+	geodataMode        bool
 	homeDir            string
 	configFile         string
 	externalUI         string
@@ -35,6 +36,7 @@ func init() {
 	flag.StringVar(&externalUI, "ext-ui", "", "override external ui directory")
 	flag.StringVar(&externalController, "ext-ctl", "", "override external controller address")
 	flag.StringVar(&secret, "secret", "", "override secret for RESTful API")
+	flag.BoolVar(&geodataMode, "m", false, "set geodata mode")
 	flag.BoolVar(&version, "v", false, "show current version of clash")
 	flag.BoolVar(&testConfig, "t", false, "test configuration and exit")
 	flag.Parse()
@@ -75,6 +77,10 @@ func main() {
 		log.Fatalln("Initial configuration directory error: %s", err.Error())
 	}
 
+	if geodataMode {
+		config.GeodataMode = true
+	}
+
 	if testConfig {
 		if _, err := executor.Parse(); err != nil {
 			log.Errorln(err.Error())