In response to water scarcity and food security, most governments in the world have adopted water-saving irrigation promotion policies by increasing the water-saving irrigation area. Many researches focus on water scarcity, but there is a lack of research on the food security effects of water-saving irrigation policies. A two-way fixed effect model was used to identify the effect of water-saving irrigation area on the production of food crops with panel data of 31 Chinese provinces from 2000 to 2019. The study shows: First, water-saving irrigation area not only can save agricultural water use, but also has a significant positive effect on production of food crops; Second, water-saving irrigation area affects production of food crops through agricultural input factors, such as sown area, chemical fertilizer, and mechanized power; Third, there is heterogeneity in the effect of water-saving irrigation area on production of food crops, in which water-saving irrigation area has a greater impact on production of food crops in areas where there is less rainfall, or lower water-saving irrigation rate. Therefore, the water-saving irrigation promotion has a significant role in promoting China’s production of food crops and has made a certain contribution to ensuring food security.