For the problem of ignoring the horizontal inhomogeneous characteristics of evaporation duct in the research of radio system performance, the non-reciprocity of evaporation duct on the condition of horizontal inhomogeneous environment is discussed. The non-uniformity characteristics are studied by the simulation of Markov process. Radio transmission losses are calculated by parabolic equation method. The impacts of radar electromagnetic parameters on non-reciprocity are analyzed. Simulation results show that the radio non-reciprocity cannot be ignored in the horizontal inhomogeneous evaporation duct environment, the effects on non-reciprocity of antenna height and frequency are great. The larger the antenna height and the radio frequency, the stronger the non-reciprocity.