Abstract: As the particular morphology and structure of bryophytes, the contents of poilutants in the bryophytes were taken as the measure of air pollution level. And the change of physiological and biochemical changes in two epiphytic bryophytes Haplocladiurn microphyllum and Entodon compressus in the six regions in Nanjing were studied. The results showed that with the gradual aggravates of air pollution, heavy metals and S element con tents in two epiphytic bryophytes increased, the total chlorophyll contents all decreased. Free proline content and cell membrane permeability all obviously increased, but the catalase activities in the tow bryophytes took different change patterns. And the impact of air pollution to physiological and biochemical changes in two epiphytic bryophytes reached 1% significant level except the the catalase activities. The physiological and biochemical changes in H. microphyllum was in a greater degree than in E. co,npressus, which showed that H. micro phyllum was more sensitive to air pollution.