diff --git a/boards/arm/stm32f3_disco/pinmux.c b/boards/arm/stm32f3_disco/pinmux.c
index 8efbf79bd1b..b64a4b2127d 100644
--- a/boards/arm/stm32f3_disco/pinmux.c
+++ b/boards/arm/stm32f3_disco/pinmux.c
@@ -15,8 +15,8 @@
 /* pin assignments for STM32F3DISCOVERY board */
 static const struct pin_config pinconf[] = {
 #ifdef CONFIG_UART_STM32_PORT_1
-	{STM32_PIN_PA9, STM32F3_PINMUX_FUNC_PA9_USART1_TX},
-	{STM32_PIN_PA10, STM32F3_PINMUX_FUNC_PA10_USART1_RX},
+	{STM32_PIN_PC4, STM32F3_PINMUX_FUNC_PC4_USART1_TX},
+	{STM32_PIN_PC5, STM32F3_PINMUX_FUNC_PC5_USART1_RX},
 #endif	/* CONFIG_UART_STM32_PORT_1 */
 #ifdef CONFIG_UART_STM32_PORT_2
 	{STM32_PIN_PA2, STM32F3_PINMUX_FUNC_PA2_USART2_TX},
diff --git a/drivers/pinmux/stm32/pinmux_stm32f3.h b/drivers/pinmux/stm32/pinmux_stm32f3.h
index 27062d11db8..a0477e7b03f 100644
--- a/drivers/pinmux/stm32/pinmux_stm32f3.h
+++ b/drivers/pinmux/stm32/pinmux_stm32f3.h
@@ -14,6 +14,9 @@
 #define STM32F3_PINMUX_FUNC_PA9_USART1_TX   STM32_PINMUX_ALT_FUNC_7 | STM32_PUSHPULL_PULLUP
 #define STM32F3_PINMUX_FUNC_PA10_USART1_RX  STM32_PINMUX_ALT_FUNC_7 | STM32_PUSHPULL_PULLUP
 
+#define STM32F3_PINMUX_FUNC_PC4_USART1_TX   STM32_PINMUX_ALT_FUNC_7 | STM32_PUSHPULL_PULLUP
+#define STM32F3_PINMUX_FUNC_PC5_USART1_RX   STM32_PINMUX_ALT_FUNC_7 | STM32_PUSHPULL_PULLUP
+
 #define STM32F3_PINMUX_FUNC_PA2_USART2_TX   STM32_PINMUX_ALT_FUNC_7 | STM32_PUSHPULL_PULLUP
 #define STM32F3_PINMUX_FUNC_PA3_USART2_RX   STM32_PINMUX_ALT_FUNC_7 | STM32_PUSHPULL_PULLUP
 
diff --git a/dts/arm/st/stm32f3-pinctrl.dtsi b/dts/arm/st/stm32f3-pinctrl.dtsi
index 4bb17ed1163..463573d7c5a 100644
--- a/dts/arm/st/stm32f3-pinctrl.dtsi
+++ b/dts/arm/st/stm32f3-pinctrl.dtsi
@@ -27,6 +27,12 @@
 					tx = <STM32_PIN_PB6 (STM32_PINMUX_ALT_FUNC_7 | STM32_PUSHPULL_NOPULL)>;
 				};
 			};
+			usart1_pins_d: usart1@3 {
+				rx_tx {
+					rx = <STM32_PIN_PC5 (STM32_PINMUX_ALT_FUNC_7 | STM32_PUPDR_NO_PULL)>;
+					tx = <STM32_PIN_PC4 (STM32_PINMUX_ALT_FUNC_7 | STM32_PUSHPULL_NOPULL)>;
+				};
+			};
 			usart2_pins_a: usart2@0 {
 				rx_tx {
 					rx = <STM32_PIN_PA3 (STM32_PINMUX_ALT_FUNC_7 | STM32_PUPDR_NO_PULL)>;
diff --git a/dts/arm/stm32f3_disco.dts b/dts/arm/stm32f3_disco.dts
index b8c97ba1ab3..fc835a29829 100644
--- a/dts/arm/stm32f3_disco.dts
+++ b/dts/arm/stm32f3_disco.dts
@@ -20,7 +20,7 @@
 
 &usart1 {
 	current-speed = <115200>;
-	pinctrl-0 = <&usart1_pins_b>;
+	pinctrl-0 = <&usart1_pins_d>;
 	pinctrl-names = "default";
 	status = "ok";
 };