To gain insight into climate change effects on main crop (wheat,corn,cotton,and peanut) water requirement of Henan province,crop water requirement were calculated according to the FAO Penman-Monteith equation.The climatic data of 12 meteorological stations from 1971 to 2010 were used to analyze the relationship between climate change and crop water requirement.The results showed that the crop water requirement was highest in June,and lowest in November or December.As for water requirement difference between the 4 crops,cotton demanded more water than wheat,which is followed by peanut,and the corn demanded least water in the 4 main crops.Crop water requirement had a tendency of decreasing from 1971 to 2001.The mean wind speed had a significantly positive influence on crop water requirement.The mean wind speed significantly decreased in the past 40 years,and resulted in the reduction of the water requirement of main crops.