PM2.5 and PM10 samples were collected on campus of Xinjiang Agricultural University during Dec. 14-28, 2009, and the speciation of Cd in PM10 and PM2.5 and its health risk index was analyzed. The results showed that the pollution caused by PM10 and PM2.5 was severe here during the heating period; Cd in PM10 and PM2.5 was of concentration 3.642 and 1.964 ng x m(-3) respectively, mainly in the form of residue; however, Cd in PM2.5 had a higher bioavailability than that in PM10. The carcinogenic risk of Cd in PM10 and PM2.5 was 6.56 x 10(-6) and 3.46 x 10(-6) respectively, which were both acceptable.