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Water saving in irrigation is a main issue in the Yellow River basin. Field studies were conducted in two areas. The Huinong system, Ningxia, in the upper reaches, where excess irrigation water is applied giving rise to waterlogging and salinity problems, and the Bojili system, Shandong, in the lower reaches of the river basin, where water availability is insufficient and salinity is related to drainage reuse. To control such problems, improved irrigation scheduling may play an important role. The irrigation scheduling simulation model ISAREG is used to evaluate the current schedules and to generate improved ones. It computes the capillary rise from the water table and deep percolation when excess water is applied, and considers the effects of salinity in crop evapotranspiration, crop water stress and yields, as well as the leaching requirements. The model has been previously calibrated and validated for North China. The model is explored interactively with surface irrigation simulation models to take into consideration the limitations imposed by the field systems concerning depths to be applied and irrigation performances. For Huinong, improvements consist in reducing the number of irrigations and adopting new calendars according to the depth of water table and the soil salinity conditions. Percolation could then be reduced from the current 60 % of the applied depths to only the volumes required for leaching. Water saving would represent more than 33 % and salinity could be controlled when also drainage would be improved. For Bojili, current schedules are appropriate and main issues concern deficit irrigation to cope with present water shortages. For both applications, it is concluded that effectiveness of irrigation scheduling improvements highly depend on required betterment in the basin irrigation systems mainly relative to land levelling, inflow discharges and field sizes.