The consumption law of soil moisture in wheat fields in the eastern part of Weibei rainfed highland was analyzed by using the farmland water balance method.The results show that the actual water consumption by wheat was 291.5~365.9mm, the rate of average moisture to meet wheat requirement was 64.9%.A mathematical model for wheat yields and farmland evapotranspiration is established through the statistics analysis.The agronomic measures such as accumulating and conservation moisture techniques, soil fertility and drought-proof chemicals are put forward.