A scanning microwave radiometer(RM)was launched on August 16,2011,on board HY-2 satellite.The six-month long global sea surface wind speeds observed by the HY-2 scanning microwave radiometer are preliminarily validated using in-situ measurements and WindSat observations,respectively,from January to June 2012.The wind speed root-mean-square(RMS)difference of the comparisons with in-situ data is1.89 m/s for the measurements of NDBC and 1.72 m/s for the recent four-month data measured by PY30-1oil platform,respectively.On a global scale,the wind speeds of HY-2 RM are compared with the sea surface wind speeds derived from WindSat,the RMS difference of 1.85 m/s for HY-2 RM collocated observations data set is calculated in the same period as above.With analyzing the global map of a mean difference between HY-2 RM and WindSat,it appears that the bias of the sea surface wind speed is obviously higher in the inshore regions.In the open sea,there is a relatively higher positive bias in the mid-latitude regions due to the overestimation of wind speed observations,while the wind speeds are underestimated in the Southern Ocean by HY-2 RM relative to WindSat observations. A scanning microwave radiometer (RM) was launched on August 16, 2011, on board HY-2 satellite. The six-month long global sea surface wind speeds by the HY-2 scanning microwave radiometer are preliminarily validated using in situ measurements and WindSat observations, respectively, from January to June 2012. The wind speed root-mean-square (RMS) difference of the comparisons with in-situ data is 1.89 m / s for the measurements of NDBC and 1.72 m / s for the recent Four-month data measured by PY30-1oil platform, respectively. An global scale, the wind speeds of HY-2 RM are compared with the sea surface wind speeds derived from WindSat, the RMS difference of 1.85 m / s for HY-2 RM collocated observations data set is calculated in the same period as above. With analyzing the global map of a mean difference between HY-2 RM and WindSat, it appears that the bias of the sea surface wind speed is obviously higher in the inshore regions. In the open sea, there is a relatively higher positive bias in the mid-l atitude regions due to the overestimation of wind speed observations, while the wind speeds are underestimated in the Southern Ocean by HY-2 RM relative to WindSat observations.