A model for water uptake by winter wheat is developed in terms of the zero-flux plane for the determination of the maximum depth of water uptake of root. Using asoil water flowing epuation governed by the temperature and moisture gradients, a nu-merical simulation is made of the time-spatial change of soil water content during theperiod from the late stage of stem elongation to the ripening stage of wheat milk in theexperimental fields of the Jingyang Weather Station in1988. Results of the simulation arecompared with the data obtained from the winter farmland and agree fairly well with ac-tual observations for a simulated period of 31 days.