diff --git a/apps/emqtt/src/emqtt_session.erl b/apps/emqtt/src/emqtt_session.erl
index 72c2757fb..2c1304e03 100644
--- a/apps/emqtt/src/emqtt_session.erl
+++ b/apps/emqtt/src/emqtt_session.erl
@@ -29,7 +29,7 @@
 %% ------------------------------------------------------------------
 %% API Function Exports
 %% ------------------------------------------------------------------
--export([start/1, resume/3, publish/2, puback/2, subscribe/2, unsubscribe/2]).
+-export([start/1, resume/3, publish/2, puback/2, subscribe/2, unsubscribe/2, destroy/2]).
 
 %%start gen_server
 -export([start_link/3]).
@@ -56,12 +56,12 @@
 %% ------------------------------------------------------------------
 %% Start Session
 %% ------------------------------------------------------------------
-start({true = CleanSess, ClientId, _ClientPid}) ->
+start({true = _CleanSess, ClientId, _ClientPid}) ->
     %%Destroy old session if CleanSess is true before.
-    ok = emqtt_sm:destory_session(ClientId),
+    ok = emqtt_sm:destroy_session(ClientId),
     {ok, initial_state(ClientId)};
 
-start({false = CleanSess, ClientId, ClientPid}) ->
+start({false = _CleanSess, ClientId, ClientPid}) ->
     {ok, SessPid} = emqtt_sm:start_session(ClientId, ClientPid),
     {ok, SessPid}.
 
@@ -146,10 +146,13 @@ unsubscribe(SessState = #session_state{client_id = ClientId, submap = SubMap}, T
     SubMap1 = lists:foldl(fun(Topic, Acc) -> maps:remove(Topic, Acc) end, SubMap, Topics),
     {ok, SessState#session_state{submap = SubMap1}};
 
-unsubscribe(SessPid, Topics) ->
+unsubscribe(SessPid, Topics) when is_pid(SessPid) ->
     gen_server:call(SessPid, {unsubscribe, Topics}),
     {ok, SessPid}.
 
+destroy(SessPid, ClientId)  when is_pid(SessPid) ->
+    gen_server:cast(SessPid, {destroy, ClientId}).
+
 initial_state(ClientId) ->
     #session_state { client_id  = ClientId,
                      packet_id  = 1, 
@@ -219,6 +222,10 @@ handle_cast({pubcomp, PacketId}, State) ->
     NewState = puback(State, {?PUBCOMP, PacketId}),
     {noreply, NewState};
 
+handle_cast({destroy, ClientId}, State = #session_state{client_id = ClientId}) ->
+    lager:warning("Session: ~s destroyed", [ClientId]),
+    {stop, normal, State};
+
 handle_cast(Msg, State) ->
     {stop, {badmsg, Msg}, State}.
 
diff --git a/apps/emqtt/src/emqtt_sm.erl b/apps/emqtt/src/emqtt_sm.erl
index 406c699be..f98dc27d3 100644
--- a/apps/emqtt/src/emqtt_sm.erl
+++ b/apps/emqtt/src/emqtt_sm.erl
@@ -55,7 +55,7 @@
 
 -export([start_link/0]).
 
--export([lookup_session/1, start_session/2, destory_session/1]).
+-export([lookup_session/1, start_session/2, destroy_session/1]).
 
 %% ------------------------------------------------------------------
 %% gen_server Function Exports
@@ -75,7 +75,7 @@
 
 -spec(start_session/2 :: (binary(), pid()) -> {ok, pid()} | {error, any()}).
 
--spec(destory_session/1 :: (binary()) -> ok).
+-spec(destroy_session/1 :: (binary()) -> ok).
 
 -endif.
 
@@ -100,8 +100,8 @@ lookup_session(ClientId) ->
 start_session(ClientId, ClientPid) ->
     gen_server:call(?SERVER, {start_session, ClientId, ClientPid}).
 
-destory_session(ClientId) ->
-    gen_server:call(?SERVER, {destory_session, ClientId}).
+destroy_session(ClientId) ->
+    gen_server:call(?SERVER, {destroy_session, ClientId}).
 
 %% ------------------------------------------------------------------
 %% gen_server Function Definitions
@@ -130,11 +130,11 @@ handle_call({start_session, ClientId, ClientPid}, _From, State) ->
     end,
     {reply, Reply, State};
 
-handle_call({destory_session, ClientId}, _From, State) ->
+handle_call({destroy_session, ClientId}, _From, State) ->
     case ets:lookup(?TABLE, ClientId) of
         [{_, SessPid, MRef}] ->
             erlang:demonitor(MRef),
-            emqtt_session:destory(SessPid),
+            emqtt_session:destory(SessPid, ClientId),
             ets:delete(?TABLE, ClientId);
         [] ->
             ignore