The Hargreaves (HG）equation, McClound (M—C) equation, Makkink (M—K) equation and Priestley—Taylor (P—T) equation were amended against the FAO 56 Penman—Monteith（PM）by using the observed meteorological data from 1970 to 2011 at Xinxiang City. Then, the calibrated equation and weather forecast data were used to predict the 10d ET0. The precision of weather forecast and forecast ET0 was evaluated, and an analytical method was developed to translate daily weather forecast message into the variables needed by estimation ET0. The results showed that the mean accuracy of calibration HG (HG—M) equation, P—T equation, M—C equation and M—K equation were relatively higher. However, the maximum and minimum air temperature, wind speed, hours of sunshine tended to decline with the increasing forecast horizon; the accuracy of minimum air temperature forecast was higher than that of the maximum air temperature. The mean accuracy of P—T model was the highest (95.06%) among all models, meanwhile, the HG—M equation, M—K model, PMT1 model were in turn. The prediction accuracy of selected four models were higher than other models, but the P—T and HG—M models could satisfy the requirement of higher accuracy and simplify the calculating procedure. So for ET0 middle and short term forecast, the P—T and HG—M models could make a great contribution to improve the accuracy of irrigation forecast.