In this study, SCIAMACHY/ENVISAT SO2 data products have been validated by ground based remote sensing instrument MAXDOAS in China. The spatial and temporal distribution of tropospheric SO2 over China is discussed in this study. The result shows that the SO2 load over East China is decreasing since strong control for pollution emission in 2007 for preparation of 2008 Olympic Games in China, while the SO2 load in West China is increasing all the way during 2004-2009, which might reflect that the anthropogenic activity was added to promote the economy development in west of China. Typical seasonal variation with high pollution levels in winter and low in summer is found in the northwest of China, while the inverse seasonal variation is found for the south of China. The characteristics of tropospheric SO2 over megacities in China were explored and the results show that tropospheric SO2 was partly under control from 2006 because of the policy from China government for reduction in SO2 emissions in 2005.