Abstract: To probe into benefit situation of land comprehensive improvement project of dryland-to-paddy conversion in Wumeng Mountain valley, and to better promote protection of cultivated land in mountainou areas and ensure food security of grain self-sufficient areas, selecting Qixingguan District, Bijie City, Guizhou Province in hinterland of Wumeng Mountain as study area, and taking comprehensive land improvement project of Gangouhe Village and Haizi Community in Yanzikou Town, Qixingguan District as examples, benefits of project to carry out combination of planting and breeding were analyzed in detail．Results showed that balance of water supply and demand, and compatibility of soil with rice planting were the most important factors for feasibility of dryland-to-paddy conversion project site selection．Main engineering measures of dryland-to-paddy conversion project in Wumeng Mountain valley included land leveling, field road project, and irrigation and drainage project．Adopting combination of rice planting and rice-fish breeding to improve economic benefits of project, raising 3000 rice-fish per hectare of paddy field could increase economic income by about 60000 yuan．Mode of combining planting and breeding is a beneficial way to improve current agricultural inefficiency, and an important way to realize sustainable development of land comprehensive improvement of dryland-to-paddy conversion in Wumeng Mountain area．