diff --git a/include/pthread.h b/include/pthread.h
index 191bbf4e8bf15..39972b91912a4 100644
--- a/include/pthread.h
+++ b/include/pthread.h
@@ -269,7 +269,8 @@ struct pthread_cond_s
 {
   sem_t sem;
   clockid_t clockid;
-  uint16_t wait_count;
+  unsigned int wait_count;
+  mutex_t mutex;
 };
 
 #ifndef __PTHREAD_COND_T_DEFINED
diff --git a/libs/libc/pthread/pthread_condinit.c b/libs/libc/pthread/pthread_condinit.c
index c174f98bb6e5e..fdcb283d555bb 100644
--- a/libs/libc/pthread/pthread_condinit.c
+++ b/libs/libc/pthread/pthread_condinit.c
@@ -31,6 +31,8 @@
 #include <debug.h>
 #include <errno.h>
 
+#include <nuttx/atomic.h>
+
 /****************************************************************************
  * Public Functions
  ****************************************************************************/
@@ -75,6 +77,7 @@ int pthread_cond_init(FAR pthread_cond_t *cond,
     {
       cond->clockid = attr ? attr->clockid : CLOCK_REALTIME;
       cond->wait_count = 0;
+      nxmutex_init(&cond->mutex);
     }
 
   sinfo("Returning %d\n", ret);
diff --git a/sched/pthread/pthread_condbroadcast.c b/sched/pthread/pthread_condbroadcast.c
index 581666548710f..2c584484e6c9a 100644
--- a/sched/pthread/pthread_condbroadcast.c
+++ b/sched/pthread/pthread_condbroadcast.c
@@ -31,6 +31,8 @@
 #include <errno.h>
 #include <debug.h>
 
+#include <nuttx/atomic.h>
+
 #include "pthread/pthread.h"
 
 /****************************************************************************
@@ -42,10 +44,7 @@
  *
  * Description:
  *    A thread broadcast on a condition variable.
- *    pthread_cond_broadcast shall unblock all threads currently blocked on a
- *    specified condition variable cond. We need own the mutex that threads
- *    calling pthread_cond_wait or pthread_cond_timedwait have associated
- *    with the condition variable during their wait.
+ *
  * Input Parameters:
  *   None
  *
@@ -68,9 +67,11 @@ int pthread_cond_broadcast(FAR pthread_cond_t *cond)
     }
   else
     {
+      nxmutex_lock(&cond->mutex);
+
       /* Loop until all of the waiting threads have been restarted. */
 
-      while (cond->wait_count > 0)
+      while (atomic_load(&cond->wait_count) > 0)
         {
           /* If the value is less than zero (meaning that one or more
            * thread is waiting), then post the condition semaphore.
@@ -83,8 +84,10 @@ int pthread_cond_broadcast(FAR pthread_cond_t *cond)
            * above post).
            */
 
-          cond->wait_count--;
+          atomic_fetch_sub(&cond->wait_count, 1);
         }
+
+      nxmutex_unlock(&cond->mutex);
     }
 
   sinfo("Returning %d\n", ret);
diff --git a/sched/pthread/pthread_condclockwait.c b/sched/pthread/pthread_condclockwait.c
index 77a62101f9adc..34e2038af961e 100644
--- a/sched/pthread/pthread_condclockwait.c
+++ b/sched/pthread/pthread_condclockwait.c
@@ -36,6 +36,7 @@
 #include <assert.h>
 #include <debug.h>
 
+#include <nuttx/atomic.h>
 #include <nuttx/irq.h>
 #include <nuttx/wdog.h>
 #include <nuttx/signal.h>
@@ -113,7 +114,7 @@ int pthread_cond_clockwait(FAR pthread_cond_t *cond,
 
       sinfo("Give up mutex...\n");
 
-      cond->wait_count++;
+      atomic_fetch_add(&cond->wait_count, 1);
 
       /* Give up the mutex */
 
diff --git a/sched/pthread/pthread_condsignal.c b/sched/pthread/pthread_condsignal.c
index 4e9055f773d97..ff3a067a5415c 100644
--- a/sched/pthread/pthread_condsignal.c
+++ b/sched/pthread/pthread_condsignal.c
@@ -30,6 +30,8 @@
 #include <errno.h>
 #include <debug.h>
 
+#include <nuttx/atomic.h>
+
 #include "pthread/pthread.h"
 
 /****************************************************************************
@@ -41,10 +43,6 @@
  *
  * Description:
  *    A thread can signal on a condition variable.
- *    pthread_cond_signal shall unblock a thread currently blocked on a
- *    specified condition variable cond. We need own the mutex that threads
- *    calling pthread_cond_wait or pthread_cond_timedwait have associated
- *    with the condition variable during their wait.
  *
  * Input Parameters:
  *   None
@@ -68,12 +66,16 @@ int pthread_cond_signal(FAR pthread_cond_t *cond)
     }
   else
     {
-      if (cond->wait_count > 0)
+      nxmutex_lock(&cond->mutex);
+
+      if (atomic_load(&cond->wait_count) > 0)
         {
           sinfo("Signalling...\n");
-          cond->wait_count--;
+          atomic_fetch_sub(&cond->wait_count, 1);
           ret = -nxsem_post(&cond->sem);
         }
+
+      nxmutex_unlock(&cond->mutex);
     }
 
   sinfo("Returning %d\n", ret);
diff --git a/sched/pthread/pthread_condwait.c b/sched/pthread/pthread_condwait.c
index ca8f05511e407..8cf53fd3cd215 100644
--- a/sched/pthread/pthread_condwait.c
+++ b/sched/pthread/pthread_condwait.c
@@ -32,6 +32,7 @@
 #include <errno.h>
 #include <debug.h>
 
+#include <nuttx/atomic.h>
 #include <nuttx/cancelpt.h>
 
 #include "pthread/pthread.h"
@@ -88,7 +89,7 @@ int pthread_cond_wait(FAR pthread_cond_t *cond, FAR pthread_mutex_t *mutex)
 
       sinfo("Give up mutex / take cond\n");
 
-      cond->wait_count++;
+      atomic_fetch_add(&cond->wait_count, 1);
       ret = pthread_mutex_breaklock(mutex, &nlocks);
 
       status = -nxsem_wait_uninterruptible(&cond->sem);