In this paper,nonlinearity characteristics and its classification in communication systemsare expatiated,In following discussion,response-characteristics of nonlinearity and its effection arequantificationally described and analysed by Volterra-series. At last,some material measures fordecreasing system nonlinear characteristics and its interference,are proposed from the point ofengineering view,which gives the corresponding theory reference to solve problems of nonlinearinterference in communication system...