diff --git a/nebula-algorithm/src/main/scala/com/vesoft/nebula/algorithm/lib/LouvainAlgo.scala b/nebula-algorithm/src/main/scala/com/vesoft/nebula/algorithm/lib/LouvainAlgo.scala
index 99b17de..854b8a1 100644
--- a/nebula-algorithm/src/main/scala/com/vesoft/nebula/algorithm/lib/LouvainAlgo.scala
+++ b/nebula-algorithm/src/main/scala/com/vesoft/nebula/algorithm/lib/LouvainAlgo.scala
@@ -365,9 +365,8 @@ object CommUtil {
   // return the collections of communities
   def getCommunities(G: Graph[VertexData, Double]): RDD[Row] = {
     val communities = G.vertices
-      .map(x => {
-        Row(x._1, x._2.cId)
-      })
+      .flatMapValues(_.innerVertices)
+      .map(value => { Row(value._2, value._1) })
     communities
   }
 }
diff --git a/nebula-algorithm/src/test/resources/edge_noWeight.csv b/nebula-algorithm/src/test/resources/edge_noWeight.csv
new file mode 100644
index 0000000..c3a22ce
--- /dev/null
+++ b/nebula-algorithm/src/test/resources/edge_noWeight.csv
@@ -0,0 +1,19 @@
+1 2
+1 7
+1 4
+2 0
+2 4
+2 5
+2 6
+3 0
+3 7
+4 0
+4 10
+5 7
+5 11
+6 7
+6 11
+8 9
+8 10
+8 11
+9 12
diff --git a/nebula-algorithm/src/test/scala/com/vesoft/nebula/algorithm/lib/LouvainAlgoSuite.scala b/nebula-algorithm/src/test/scala/com/vesoft/nebula/algorithm/lib/LouvainAlgoSuite.scala
index 06aa3ed..293f26e 100644
--- a/nebula-algorithm/src/test/scala/com/vesoft/nebula/algorithm/lib/LouvainAlgoSuite.scala
+++ b/nebula-algorithm/src/test/scala/com/vesoft/nebula/algorithm/lib/LouvainAlgoSuite.scala
@@ -18,5 +18,13 @@ class LouvainAlgoSuite {
     val louvainConfig = new LouvainConfig(5, 2, 1.0)
     val louvainResult = LouvainAlgo.apply(spark, data, louvainConfig, false)
     assert(louvainResult.count() == 4)
+
+    val dataWithoutWith = spark.read
+      .option("header", false)
+      .option("delimiter", " ")
+      .csv("src/test/resources/edge_noWeight.csv")
+      .select("_c0", "_c1")
+    val louvainResult1 = LouvainAlgo.apply(spark, dataWithoutWith, louvainConfig, false)
+    assert(louvainResult1.count() == 13)
   }
 }