diff --git a/tests/drivers/adc/adc_api/boards/gd32a503v_eval.overlay b/tests/drivers/adc/adc_api/boards/gd32a503v_eval.overlay
new file mode 100644
index 00000000000000..33be52c9309680
--- /dev/null
+++ b/tests/drivers/adc/adc_api/boards/gd32a503v_eval.overlay
@@ -0,0 +1,27 @@
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Copyright (c) 2023 Benjamin Björnsson <benjamin.bjornsson@gmail.com>
+ */
+
+#include <zephyr/dt-bindings/adc/adc.h>
+
+/ {
+	zephyr,user {
+		/* adjust channel number according to pinmux in board.dts */
+		io-channels = <&adc0 1>;
+	};
+};
+
+&adc0 {
+	#address-cells = <1>;
+	#size-cells = <0>;
+
+	channel@1 {
+		reg = <1>;
+		zephyr,gain = "ADC_GAIN_1";
+		zephyr,reference = "ADC_REF_INTERNAL";
+		zephyr,acquisition-time = <ADC_ACQ_TIME_DEFAULT>;
+		zephyr,resolution = <12>;
+	};
+};
diff --git a/tests/drivers/adc/adc_api/src/test_adc.c b/tests/drivers/adc/adc_api/src/test_adc.c
index 05bfb34d3a61c3..b49b6339358ab9 100644
--- a/tests/drivers/adc/adc_api/src/test_adc.c
+++ b/tests/drivers/adc/adc_api/src/test_adc.c
@@ -19,15 +19,6 @@
 #define ADC_1ST_CHANNEL_ID	0
 #define ADC_2ND_CHANNEL_ID	1
 
-#elif defined(CONFIG_BOARD_GD32A503V_EVAL)
-
-#define ADC_DEVICE_NODE		DT_INST(0, gd_gd32_adc)
-#define ADC_RESOLUTION		12
-#define ADC_GAIN		ADC_GAIN_1
-#define ADC_REFERENCE		ADC_REF_INTERNAL
-#define ADC_ACQUISITION_TIME	ADC_ACQ_TIME_DEFAULT
-#define ADC_1ST_CHANNEL_ID	1
-
 #elif defined(CONFIG_BOARD_SAM_E70_XPLAINED) || \
 	defined(CONFIG_BOARD_SAM_V71_XULT)