diff --git a/sched/pthread/pthread_join.c b/sched/pthread/pthread_join.c
index 994bc7d5a1..328708bc31 100644
--- a/sched/pthread/pthread_join.c
+++ b/sched/pthread/pthread_join.c
@@ -137,6 +137,15 @@ int pthread_join(pthread_t thread, FAR pthread_addr_t *pexit_value)
     }
   else
     {
+      /* NOTE: sched_lock() is not enough for SMP
+       * because another CPU would continue the pthread and exit
+       * sequences so need to protect it with a critical section
+       */
+
+#ifdef CONFIG_SMP
+      irqstate_t flags = enter_critical_section();
+#endif
+
       /* We found the join info structure.  Increment for the reference
        * to the join structure that we have.  This will keep things
        * stable for we have to do
@@ -211,6 +220,10 @@ int pthread_join(pthread_t thread, FAR pthread_addr_t *pexit_value)
 
       sched_unlock();
 
+#ifdef CONFIG_SMP
+      leave_critical_section(flags);
+#endif
+
       /* Release our reference to the join structure and, if the reference
        * count decrements to zero, deallocate the join structure.
        */