diff --git a/internal/core/src/exec/operator/RandomSampleNode.cpp b/internal/core/src/exec/operator/RandomSampleNode.cpp
index b3d46f98f9..d95e89ef04 100644
--- a/internal/core/src/exec/operator/RandomSampleNode.cpp
+++ b/internal/core/src/exec/operator/RandomSampleNode.cpp
@@ -101,6 +101,10 @@ PhyRandomSampleNode::GetOutput() {
         return nullptr;
     }
 
+    std::chrono::high_resolution_clock::time_point start =
+        std::chrono::high_resolution_clock::now();
+
+    RowVectorPtr result = nullptr;
     if (!is_source_node_) {
         auto input_col = GetColumnVector(input_);
         TargetBitmapView input_data(input_col->GetRawData(), input_col->size());
@@ -126,8 +130,7 @@ PhyRandomSampleNode::GetOutput() {
             }
         }
 
-        is_finished_ = true;
-        return std::make_shared<RowVector>(std::vector<VectorPtr>{input_col});
+        result = std::make_shared<RowVector>(std::vector<VectorPtr>{input_col});
     } else {
         auto sample_output = std::make_shared<ColumnVector>(
             TargetBitmap(active_count_), TargetBitmap(active_count_));
@@ -152,10 +155,18 @@ PhyRandomSampleNode::GetOutput() {
             data.flip();
         }
 
-        is_finished_ = true;
-        return std::make_shared<RowVector>(
-            std::vector<VectorPtr>{sample_output});
+        result =
+            std::make_shared<RowVector>(std::vector<VectorPtr>{sample_output});
     }
+
+    std::chrono::high_resolution_clock::time_point end =
+        std::chrono::high_resolution_clock::now();
+    double duration =
+        std::chrono::duration<double, std::micro>(end - start).count();
+    monitor::internal_core_search_latency_random_sample.Observe(duration /
+                                                                1000);
+    is_finished_ = true;
+    return result;
 }
 
 bool
diff --git a/internal/core/src/monitor/prometheus_client.cpp b/internal/core/src/monitor/prometheus_client.cpp
index bab294c4e3..50027dc4c0 100644
--- a/internal/core/src/monitor/prometheus_client.cpp
+++ b/internal/core/src/monitor/prometheus_client.cpp
@@ -208,6 +208,8 @@ std::map<std::string, std::string> retrieveGetTargetEntryLatencyLabels{
     {"type", "retrieve_get_target_entry_latency"}};
 std::map<std::string, std::string> searchGetTargetEntryLatencyLabels{
     {"type", "search_get_target_entry_latency"}};
+std::map<std::string, std::string> randomSampleLatencyLabels{
+    {"type", "random_sample_latency"}};
 
 DEFINE_PROMETHEUS_HISTOGRAM_FAMILY(internal_core_search_latency,
                                    "[cpp]latency(us) of search on segment")
@@ -237,6 +239,10 @@ DEFINE_PROMETHEUS_HISTOGRAM(internal_core_retrieve_get_target_entry_latency,
 DEFINE_PROMETHEUS_HISTOGRAM(internal_core_search_get_target_entry_latency,
                             internal_core_search_latency,
                             searchGetTargetEntryLatencyLabels)
+DEFINE_PROMETHEUS_HISTOGRAM(internal_core_search_latency_random_sample,
+                            internal_core_search_latency,
+                            randomSampleLatencyLabels)
+
 // mmap metrics
 std::map<std::string, std::string> mmapAllocatedSpaceAnonLabel = {
     {"type", "anon"}};
diff --git a/internal/core/src/monitor/prometheus_client.h b/internal/core/src/monitor/prometheus_client.h
index e10bc2618b..758815a290 100644
--- a/internal/core/src/monitor/prometheus_client.h
+++ b/internal/core/src/monitor/prometheus_client.h
@@ -141,6 +141,7 @@ DECLARE_PROMETHEUS_HISTOGRAM(internal_core_search_latency_scalar_proportion);
 DECLARE_PROMETHEUS_HISTOGRAM(internal_core_get_vector_latency);
 DECLARE_PROMETHEUS_HISTOGRAM(internal_core_retrieve_get_target_entry_latency);
 DECLARE_PROMETHEUS_HISTOGRAM(internal_core_search_get_target_entry_latency);
+DECLARE_PROMETHEUS_HISTOGRAM(internal_core_search_latency_random_sample);
 
 // async cgo metrics
 DECLARE_PROMETHEUS_HISTOGRAM_FAMILY(internal_cgo_queue_duration_seconds);