Since the beginning of the last century in 80s the full implementation of the household contract management，small scale，decentralized management model can realize the modernization of agriculture has been questioned，Chinese agricultural modernization must find another way in expanding the scale of land outside.Many through the increasingly perfect social services to enhance the scale of agricultural benefits，some documents call it “service scale”.Exploration of Shandong Province Supply and marketing cooperative system in the reform process of the land trust model，the farmers' professional cooperatives as the organizational basis，taking the market as the direction of development，the initiative to promote the supply and marketing cooperatives，through the government，to form a powerful force to serve the farmers，is a useful practice of government power and the combination of market forces to promote the development of modern agriculture.