Abstract: Changes of chlorophyll and carotenoid content, SOD, MDA, proline content in leaves of 5 emerged plants (Iris pseudacorus, Pontederia cordata, Typha orientalis, Thalia dealbata and Spiked loosestrlfe) under sewage submerging were studied by potted plant experiments, and their effects of purifying sewage were discussed by analyzing 6 water quality parameters: TN, NH+4-N, (NO-3-N＋NO-2-N), TP and COD. The results were as follows: the chlorophyll content of 5 emerged plants fluctuated at the initial submerging period, but declined towards the end of sewage submerging, the carotenoid content had the similar tendency. During 15th-30th day after submerging, the change of SOD activity of both I. pseudacorus and S. loosestrlfe was little, and that of other plants went down, but SOD activity of whole plants increased after 45 days of submerging, and MDA content had a trend of rising at the later submerging period even though the change was not very acute in 15-30 days of submerging. The proline content of I. pseudacorus and P. cordata varied greatly, and that of other plants were not evident. The results from the comparation of physiological responses of five emerged plants showed T. orientalis, which wasnt sensitive to sewage submerging, was an more enduring specie to sewage submerging. On the other hand, the removal rates of T. dealbata to TN was 61.75 %, that of T. orientalis to TP was 87.50 %, so they were fine water punfication plant.