Abstract: The mutagenicit of pollutants in the air in Yancheng was detected by the micronucleus tests in vicia faba leave tip cells,mice bone－marrow cells and human lymphocytes.The results showed that there exist some different levels of pollution in the industrial,commercial,and residential districts,with Atmospheric Pollution Indexes or Individual Damage Indexes all more than 1.5. The air pollution in the industrial district is heaviest with the maximal Air Pollution Index of 4.48(mice bone－marrow micronucleus test).There is no pollution in the teaching area,with Atmospheric Pollution Indexes or Individual Damage Index less than 1.5.In addition,it was found that good direct correlation exist between the human lymphocytes and vicia faba leave tip cells in micronucleus effect and between the human lymphocytes and mice bone－marrow cells in micronucleus effect (P<0.005).Micronucleus test is also more sensitive and feasible than chemical monitoring for the detection of pollutants in the air.