Abstract:In North China, in order to obtain high and stable grain yield of winter wheat, irrigation should be applied during its growing season. However, water resource is very shortage and irrigation water use efficiency is very low. Therefore, irrigation frequency should be adopted in this region. In 2006-2008, an experiment was conducted at Luancheng Experimental Station of CAS to study irrigation frequency on grain yield, water use efficiency (WUE), protein yield, wet gluten content, development time, and stability time of winter wheat under irrigation frequency by variety Kenong “9204”. The results showed that irrigated at jointing, heading, and milking stages were in favor of increased grain yield, dry matter accumulation, or 1000 kernel weight, respectively. The highest grain yield was obtained in case of the treatment was irrigated 60 mm at jointing and heading stages, respectively. Irrigated two times during the growing stages of winter wheat could increase protein yield; however, irrigation timing during the later part of the growing season of winter wheat could decrease the protein yield. The results indicated that irrigation timing in the later part of the growing season and the increase in the times of irrigation, wet gluten content, development time, and stability time were all significantly decreased. On the basis of the experimental results, it is suggested that irrigation should be applied at jointing and heading stages of winter wheat to obtain reasonable grain yield, WUE, and quality under irrigation frequency in North China.