Abstract: To map risk of exposure to A/H1N1 flu in China and assess the ability of national interventions and vaccine to control dispersion of the disease.The data on China of every province of A/H1N1 flu from May 2009 to March 2010 were used to map spatial clusters and spatial autocorrelations.Getis's G* was used to detect the high-risk regions for A/H1N1 in China.The spatial clustering of A/H1N1 in China tends to be stronger gradually,that the epidemic has experienced the process from random(from May to Aug.2009),pervasion(from Sept.to Nov.2009) to concentration(from Dec.2009 to March 2010);Guangdong,Beijing and Zhejiang province are the most serious regions of the A/H1N1 outbreak there are a few adjacent provinces with high-high epidemic correlated,the hotspots of the epidemic include Shanghai,Zhejiang,Jiangsu,Fujian and other provinces in central and eastern China,while the center does not move with time goes by.It showed that A/H1N1 has a very high ratio in Nov.2009 to Dec.2009.It is the season that ordinary flu also has a very high ratio.National control measures and vaccine can be very effective at reducing transmission of A/H1N1 flu.