diff --git a/internal/distributed/rootcoord/client/paramtable_test.go b/internal/distributed/rootcoord/client/paramtable_test.go
index b4f0900e83..7b95d43b1e 100644
--- a/internal/distributed/rootcoord/client/paramtable_test.go
+++ b/internal/distributed/rootcoord/client/paramtable_test.go
@@ -14,7 +14,9 @@ package grpcrootcoordclient
 import (
 	"testing"
 
+	"github.com/milvus-io/milvus/internal/distributed/grpcconfigs"
 	"github.com/milvus-io/milvus/internal/log"
+	"github.com/stretchr/testify/assert"
 	"go.uber.org/zap"
 )
 
@@ -23,4 +25,12 @@ func TestParamTable(t *testing.T) {
 
 	log.Info("TestParamTable", zap.Int("ClientMaxSendSize", Params.ClientMaxSendSize))
 	log.Info("TestParamTable", zap.Int("ClientMaxRecvSize", Params.ClientMaxRecvSize))
+
+	Params.Remove("rootCoord.grpc.clientMaxSendSize")
+	Params.initClientMaxSendSize()
+	assert.Equal(t, Params.ClientMaxSendSize, grpcconfigs.DefaultClientMaxSendSize)
+
+	Params.Remove("rootCoord.grpc.clientMaxRecvSize")
+	Params.initClientMaxRecvSize()
+	assert.Equal(t, Params.ClientMaxRecvSize, grpcconfigs.DefaultClientMaxRecvSize)
 }
diff --git a/internal/distributed/rootcoord/param_table_test.go b/internal/distributed/rootcoord/param_table_test.go
index c340ea54bc..41335a8d28 100644
--- a/internal/distributed/rootcoord/param_table_test.go
+++ b/internal/distributed/rootcoord/param_table_test.go
@@ -14,6 +14,7 @@ package grpcrootcoord
 import (
 	"testing"
 
+	"github.com/milvus-io/milvus/internal/distributed/grpcconfigs"
 	"github.com/milvus-io/milvus/internal/log"
 	"go.uber.org/zap"
 
@@ -40,4 +41,12 @@ func TestParamTable(t *testing.T) {
 
 	log.Info("TestParamTable", zap.Int("ServerMaxSendSize", Params.ServerMaxSendSize))
 	log.Info("TestParamTable", zap.Int("ServerMaxRecvSize", Params.ServerMaxRecvSize))
+
+	Params.Remove("rootCoord.grpc.ServerMaxSendSize")
+	Params.initServerMaxSendSize()
+	assert.Equal(t, Params.ServerMaxSendSize, grpcconfigs.DefaultServerMaxSendSize)
+
+	Params.Remove("rootCoord.grpc.ServerMaxRecvSize")
+	Params.initServerMaxRecvSize()
+	assert.Equal(t, Params.ServerMaxRecvSize, grpcconfigs.DefaultServerMaxRecvSize)
 }