diff --git a/TestON/drivers/common/cli/onosclidriver.py b/TestON/drivers/common/cli/onosclidriver.py
index dcd045b..00fe9bf 100755
--- a/TestON/drivers/common/cli/onosclidriver.py
+++ b/TestON/drivers/common/cli/onosclidriver.py
@@ -2660,14 +2660,20 @@
             main.cleanup()
             main.exit()
 
-    def FlowAddedCount( self, deviceId ):
+    def flowAddedCount( self, deviceId, core=False ):
         """
         Determine the number of flow rules for the given device id that are
         in the added state
+        Params:
+            core: if True, only return the number of core flows added
         """
         try:
-            cmdStr = "flows any " + str( deviceId ) + " | " +\
-                     "grep 'state=ADDED' | wc -l"
+            if core:
+                cmdStr = "flows any " + str( deviceId ) + " | " +\
+                         "grep 'state=ADDED' | grep org.onosproject.core | wc -l"
+            else:
+                cmdStr = "flows any " + str( deviceId ) + " | " +\
+                         "grep 'state=ADDED' | wc -l"
             handle = self.sendline( cmdStr )
             assert "Command not found:" not in handle, handle
             return handle
diff --git a/TestON/tests/CHOTestMonkey/CHOTestMonkey.params b/TestON/tests/CHOTestMonkey/CHOTestMonkey.params
index 6c9ef4b..85b2e0e 100644
--- a/TestON/tests/CHOTestMonkey/CHOTestMonkey.params
+++ b/TestON/tests/CHOTestMonkey/CHOTestMonkey.params
@@ -94,6 +94,8 @@
             <CLIParamNum>0</CLIParamNum>
             <rerunInterval>5</rerunInterval>
             <maxRerunNum>5</maxRerunNum>
+            <coreFlowNum>4</coreFlowNum>
+            <coreFlowNum6>6</coreFlowNum6>
         </FlowCheck>
 
         <TrafficCheck>
diff --git a/TestON/tests/CHOTestMonkey/dependencies/events/CheckEvent.py b/TestON/tests/CHOTestMonkey/dependencies/events/CheckEvent.py
index aad520c..6b0080f 100755
--- a/TestON/tests/CHOTestMonkey/dependencies/events/CheckEvent.py
+++ b/TestON/tests/CHOTestMonkey/dependencies/events/CheckEvent.py
@@ -46,9 +46,27 @@
     def startCheckEvent( self, args=None ):
         import json
         checkResult = EventStates().PASS
+        if main.enableIPv6:
+            coreFlowNum = main.params[ 'EVENT' ][ 'FlowCheck' ][ 'coreFlowNum6' ]
+        else:
+            coreFlowNum = main.params[ 'EVENT' ][ 'FlowCheck' ][ 'coreFlowNum' ]
         for controller in main.controllers:
             if controller.isUp():
                 with controller.CLILock:
+                    # Check core flow number
+                    for device in main.devices:
+                        if device.isRemoved():
+                            continue
+                        coreFlowNumOnos = controller.CLI.flowAddedCount( device.dpid, core=True )
+                        if coreFlowNumOnos == None:
+                            main.log.warn( "Flow Check - error when trying to get flow number of %s on ONOS%s" % ( device.dpid, controller.index ) )
+                            checkResult = EventStates().FAIL
+                        else:
+                            coreFlowNumOnos = int( coreFlowNumOnos )
+                            if coreFlowNumOnos != coreFlowNum:
+                                main.log.warn( "Flow Check - core flow number of %s on ONOS%s is %s" % ( device.dpid, controller.index, coreFlowNumOnos ) )
+                                checkResult = EventStates().FAIL
+                    # Get flows for comparison
                     flows = controller.CLI.flows()
                     try:
                         flows = json.loads( flows )