diff --git a/hw/bsp/gd32vf103_longan_nano/gd32vf103_longan_nano.c b/hw/bsp/gd32vf103_longan_nano/gd32vf103_longan_nano.c
index e15d4e2b2..951ab844c 100644
--- a/hw/bsp/gd32vf103_longan_nano/gd32vf103_longan_nano.c
+++ b/hw/bsp/gd32vf103_longan_nano/gd32vf103_longan_nano.c
@@ -39,7 +39,9 @@ void USBFS_IRQHandler(void) { tud_int_handler(0); }
 
 #define USB_NO_VBUS_PIN
 
-#define TIMER_TICKS         (SystemCoreClock / 1000)
+// According to GD32VF103 user manual clock tree:
+// Systick clock = AHB clock / 4.
+#define TIMER_TICKS         ((SystemCoreClock / 4) / 1000) 
 
 #define BUTTON_PORT         GPIOA
 #define BUTTON_PIN          GPIO_PIN_0