diff --git a/src/posix/platform/system.cpp b/src/posix/platform/system.cpp
index d7ca3002f..cd5a8897d 100644
--- a/src/posix/platform/system.cpp
+++ b/src/posix/platform/system.cpp
@@ -140,7 +140,7 @@ otInstance *otSysInit(otPlatformConfig *aPlatformConfig)
 #if OPENTHREAD_CONFIG_PLATFORM_NETIF_ENABLE
     platformNetifInit(instance, aPlatformConfig->mInterfaceName);
 #elif OPENTHREAD_CONFIG_PLATFORM_UDP_ENABLE
-    ot::Posix::Udp::Init(instance, aPlatformConfig->mInterfaceName);
+    ot::Posix::Udp::Get().Init(instance, aPlatformConfig->mInterfaceName);
 #else
     gNetifName[0] = '\0';
 #endif