diff --git a/adapters/outbound/shadowsocks.go b/adapters/outbound/shadowsocks.go
index 3943c060..f743f4df 100644
--- a/adapters/outbound/shadowsocks.go
+++ b/adapters/outbound/shadowsocks.go
@@ -72,7 +72,7 @@ func (ss *ShadowSocks) Generator(metadata *C.Metadata) (adapter C.ProxyAdapter,
 }
 
 func NewShadowSocks(option ShadowSocksOption) (*ShadowSocks, error) {
-	server := fmt.Sprintf("%s:%d", option.Server, option.Port)
+	server := net.JoinHostPort(option.Server, strconv.Itoa(option.Port))
 	cipher := option.Cipher
 	password := option.Password
 	ciph, err := core.PickCipher(cipher, nil, password)
diff --git a/adapters/outbound/socks5.go b/adapters/outbound/socks5.go
index eae61090..d3a3f64b 100644
--- a/adapters/outbound/socks5.go
+++ b/adapters/outbound/socks5.go
@@ -7,6 +7,7 @@ import (
 	"fmt"
 	"io"
 	"net"
+	"strconv"
 
 	C "github.com/Dreamacro/clash/constant"
 
@@ -114,7 +115,7 @@ func NewSocks5(option Socks5Option) *Socks5 {
 	}
 
 	return &Socks5{
-		addr:           fmt.Sprintf("%s:%d", option.Server, option.Port),
+		addr:           net.JoinHostPort(option.Server, strconv.Itoa(option.Port)),
 		name:           option.Name,
 		tls:            option.TLS,
 		skipCertVerify: option.SkipCertVerify,
diff --git a/adapters/outbound/vmess.go b/adapters/outbound/vmess.go
index 68e65509..6969c3c4 100644
--- a/adapters/outbound/vmess.go
+++ b/adapters/outbound/vmess.go
@@ -68,7 +68,7 @@ func NewVmess(option VmessOption) (*Vmess, error) {
 		AlterID:        uint16(option.AlterID),
 		Security:       security,
 		TLS:            option.TLS,
-		Host:           fmt.Sprintf("%s:%d", option.Server, option.Port),
+		Host:           net.JoinHostPort(option.Server, strconv.Itoa(option.Port)),
 		NetWork:        option.Network,
 		WebSocketPath:  option.WSPath,
 		SkipCertVerify: option.SkipCertVerify,
@@ -80,7 +80,7 @@ func NewVmess(option VmessOption) (*Vmess, error) {
 
 	return &Vmess{
 		name:   option.Name,
-		server: fmt.Sprintf("%s:%d", option.Server, option.Port),
+		server: net.JoinHostPort(option.Server, strconv.Itoa(option.Port)),
 		client: client,
 	}, nil
 }