Through site monitoring water quality in Fenghe River before and after rain,the paper analyzed the water quality pollution characteristics.The results showed that non-point source pollution caused by rainfall affected TN markedly,change in nitrate nitrogen(NO3-) had good relativity with total nitrogen(TN) in the process of rainfall.NO3-is the main existence form of TN pollution in Fenghe River witch mainly come from farmland,soil and water leaching loss and urban runoff.Ammonia nitrogen(NH4+)and COD polluti...