diff --git a/targets/TARGET_STM/TARGET_STM32G0/TARGET_STM32G031xx/TARGET_NUCLEO_G031K8/PinNames.h b/targets/TARGET_STM/TARGET_STM32G0/TARGET_STM32G031xx/TARGET_NUCLEO_G031K8/PinNames.h
index 5f3e73f3d6..902354bbc1 100644
--- a/targets/TARGET_STM/TARGET_STM32G0/TARGET_STM32G031xx/TARGET_NUCLEO_G031K8/PinNames.h
+++ b/targets/TARGET_STM/TARGET_STM32G0/TARGET_STM32G031xx/TARGET_NUCLEO_G031K8/PinNames.h
@@ -155,6 +155,7 @@ typedef enum {
     D10         = PB_9,
     D11         = PB_5,
     D12         = PB_4,
+    D13         = PB_3,
 
     // STDIO for console print
 #ifdef MBED_CONF_TARGET_STDIO_UART_TX