diff --git a/src/ncp/ncp_openthread.cpp b/src/ncp/ncp_openthread.cpp
index 0f4302c28d0..0c27a9f8d25 100644
--- a/src/ncp/ncp_openthread.cpp
+++ b/src/ncp/ncp_openthread.cpp
@@ -286,7 +286,7 @@ void ControllerOpenThread::Deinit(void)
 {
     assert(mInstance != nullptr);
 
-    otSysDeinit();
+    otSysDeinit(mInstance);
     mInstance = nullptr;
 }
 
@@ -351,7 +351,7 @@ void ControllerOpenThread::Reset(void)
 {
     gPlatResetReason = OT_PLAT_RESET_REASON_SOFTWARE;
 
-    otSysDeinit();
+    otSysDeinit(mInstance);
     mInstance = nullptr;
 
     Init();