Two monthly datasets of sea surface temperature (SST),TMI SST retrieved from satellite observations by Remote Sensing System and HadISST1 (Hadley Centre Sea-ice and Sea-surface Temperature Data Set Version 1) derived from in situ measurements by Hadley Centre,were compared on climatologic multiple time scales over tropical and subtropical areas from 1998 to 2006.Results indicate that there is a good consistency in the horizontal global distribution,with 1.0° resolution on multi-year and multi-season mean scales between the two datasets,and also in the time series of global mean SST anomalies.However,there are still some significant differences between the datasets.Generally,TMI SST is relatively higher than HadISST1.In addition,the differences between the two datasets show not only remarkable regionality,but also distinct seasonal variations.Moreover,the maximum departure occurs in summer,while theminimum takes place in autumn.For all seasons,over 30% of the regions in the Tropical and Subtropical areas have a difference of more than 0.3°C.EOF analysis of the SST anomaly field also shows that there are differences between the two datasets,where HadISST1 has more significant statistical characteristics than TMI SST.On the other hand,results show that the difference between the two datasets is related to the vertical structure of ocean temperatures,as well as other simultaneously retrieved parameters in TMI products,such as wind speed,water vapor,liquid cloud water and rain rates.In addition,large biases between HadISST1 and TMI SST are found in coastal regions,where TMI SST cannot be accurately retrieved because of polluted microwave signals. Two monthly datasets of sea surface temperature (SST), TMI SST retrieved from satellite observations by Remote Sensing System and HadISST1 (Hadley Center Sea-ice and Sea-surface Temperature Data Set Version 1) derived from in situ measurements by Hadley Center, were compared on climatologic multiple time scales over tropical and subtropical areas from 1998 to 2006. Results aggregate that with a good consistency in the horizontal global distribution, with 1.0 ° resolution on multi-year and multi-season mean scales between the two datasets, and also in the time series of global mean SST anomalies. There are still some significant differences between the datasets. Normal, TMI SST is relatively higher than HadISST1.In addition, the differences between the two datasets show not only remarkable regionality, but also distinct the seasonal variations.Moreover, the maximum departure occurs in summer, while theminmost takes place in autumn.For all seasons, over 30% of the regions in the Tropical an d Subtropical areas have a difference of more than 0.3 ° C. EOF analysis of the SST anomaly field also shows that there are differences between the two datasets, where HadISST1 has more significant statistical characteristics than TMI SST.On the other hand, results show that the difference between the two datasets is related to the vertical structure of ocean temperatures, as well as other just retrieved parameters in TMI products, such as wind speed, water vapor, liquid cloud water and rain rates. In addition, large biases between HadISST1 and TMI SST are found in coastal regions, where TMI SST can not be accurately established because of polluted microwave signals.