The 10 m wind from QuikSCAT and ASCAT orbital data were compared with buoy wind data in the northern South China Sea. The results show that the two satellite data have a good applicability in the northern South China Sea. The QuikSCAT inversion wind speed is 0.46 m·s-1 higher than the buoy wind and ASCAT inversion wind speed is 0.45 m·s-1 higher than buoy wind speed in the offshore sea, though it is 0.07 m·s-1 in the open sea. The absolute error ＜30° of QuikSCAT satellite inversion wind exceeds 50％.The absolute error ＜30° of ASCAT satellite inversion wind passes 56％ in the offshore sea and gets to 64％ in the open sea. When the wind speed is small, satellite inversion wind speed is bigger, when the wind speed is fast, satellite wind speed is slower than the buoy wind. The error in the morning is bigger than that in the evening. But under the condition of 5-10 m·s-1 wind speed, the consistency of the two satellite wind data is better. The offshore wind power resource simulated by WRF model is perhaps overrated. Satellite data may be a beneficial supplement for assessing offshore wind power resource. The satellite inversion wind error analysis also provides a reference for the data assimilation of satellite inversion wind field.