Abstract: Based on the field experiment data of winter wheat blending irrigation by saline water in Nanpi Ecological Agriculture Experimental Station of the Chinese Academy of Sciences from 2002 to 2005, the effects of blending irrigation with mineralization of 0.84, 3, 4 and 5 g/L on the soil salification rate, soil sodium adsorption ratio of soil saturation extract as well as winter wheat yield and yield constitute factors irrigated were studied in order to determine upper limit of irrigation mineralization suitable for the location. The results show that because of saline water blending irrigation, the soil salt is cumulated, salification degree has positive correlation with irrigation water mineralization, soil sodium adsorption ratio increase and its impacted depths are different with mineralization degrees. The results of winter wheat yield and yield constitute factors show that irrigation water mineralization degree shouldn't exceed 3 g/L at non-drought years, measures for remiting salinity threatening must be taken in drought years, water use efficiency has negative correlation with mineralization degree. Mineralization degree should be less than 3 g/L consider of different kinds factors.