diff --git a/components/drivers/include/drivers/sensor.h b/components/drivers/include/drivers/sensor.h
index e05006f9f6..ede8d11c99 100644
--- a/components/drivers/include/drivers/sensor.h
+++ b/components/drivers/include/drivers/sensor.h
@@ -90,8 +90,6 @@ extern "C" {
 #define  RT_SENSOR_UNIT_PPB            (15) /* Concentration           unit: ppb        */
 #define  RT_SENSOR_UNIT_DMS            (16) /* Coordinates             unit: DMS        */
 #define  RT_SENSOR_UNIT_DD             (17) /* Coordinates             unit: DD         */
-#define  RT_SENSOR_UNIT_PERCENT        (18) /* Percentage              unit: %          */
-
 /* Sensor communication interface types */
 
 #define  RT_SENSOR_INTF_I2C            (1 << 0)
@@ -219,7 +217,7 @@ struct rt_sensor_data
         rt_int32_t           force;         /* Force sensor.        unit: mN          */
         rt_uint32_t          dust;          /* Dust sensor.         unit: ug/m3       */
         rt_uint32_t          eco2;          /* eCO2 sensor.         unit: ppm         */
-        rt_uint32_t          spo2;          /* SpO2 sensor.         unit: %           */
+        rt_uint32_t          spo2;          /* SpO2 sensor.         unit: permillage  */
     } data;
 };