diff --git a/cmd/sing-box/cmd_merge.go b/cmd/sing-box/cmd_merge.go
index 82c92a45..0aff7501 100644
--- a/cmd/sing-box/cmd_merge.go
+++ b/cmd/sing-box/cmd_merge.go
@@ -10,6 +10,7 @@ import (
 	C "github.com/sagernet/sing-box/constant"
 	"github.com/sagernet/sing-box/log"
 	"github.com/sagernet/sing-box/option"
+	"github.com/sagernet/sing/common"
 	E "github.com/sagernet/sing/common/exceptions"
 	"github.com/sagernet/sing/common/rw"
 
@@ -120,18 +121,18 @@ func mergeTLSInboundOptions(options *option.InboundTLSOptions) *option.InboundTL
 	}
 	if options.CertificatePath != "" {
 		if content, err := os.ReadFile(options.CertificatePath); err == nil {
-			options.Certificate = strings.Split(string(content), "\n")
+			options.Certificate = trimStringArray(strings.Split(string(content), "\n"))
 		}
 	}
 	if options.KeyPath != "" {
 		if content, err := os.ReadFile(options.KeyPath); err == nil {
-			options.Key = strings.Split(string(content), "\n")
+			options.Key = trimStringArray(strings.Split(string(content), "\n"))
 		}
 	}
 	if options.ECH != nil {
 		if options.ECH.KeyPath != "" {
 			if content, err := os.ReadFile(options.ECH.KeyPath); err == nil {
-				options.ECH.Key = strings.Split(string(content), "\n")
+				options.ECH.Key = trimStringArray(strings.Split(string(content), "\n"))
 			}
 		}
 	}
@@ -144,13 +145,13 @@ func mergeTLSOutboundOptions(options *option.OutboundTLSOptions) *option.Outboun
 	}
 	if options.CertificatePath != "" {
 		if content, err := os.ReadFile(options.CertificatePath); err == nil {
-			options.Certificate = strings.Split(string(content), "\n")
+			options.Certificate = trimStringArray(strings.Split(string(content), "\n"))
 		}
 	}
 	if options.ECH != nil {
 		if options.ECH.ConfigPath != "" {
 			if content, err := os.ReadFile(options.ECH.ConfigPath); err == nil {
-				options.ECH.Config = strings.Split(string(content), "\n")
+				options.ECH.Config = trimStringArray(strings.Split(string(content), "\n"))
 			}
 		}
 	}
@@ -159,9 +160,15 @@ func mergeTLSOutboundOptions(options *option.OutboundTLSOptions) *option.Outboun
 
 func mergeSSHOutboundOptions(options option.SSHOutboundOptions) option.SSHOutboundOptions {
 	if options.PrivateKeyPath != "" {
-		if content, err := os.ReadFile(options.PrivateKeyPath); err == nil {
-			options.PrivateKey = strings.Split(string(content), "\n")
+		if content, err := os.ReadFile(os.ExpandEnv(options.PrivateKeyPath)); err == nil {
+			options.PrivateKey = trimStringArray(strings.Split(string(content), "\n"))
 		}
 	}
 	return options
 }
+
+func trimStringArray(array []string) []string {
+	return common.Filter(array, func(it string) bool {
+		return strings.TrimSpace(it) != ""
+	})
+}