Abstract: This paper discussed the necessity， difficulty and implementation approach of the fallow system in order to solve the problems that a large number of cultivated lands has been abandoned or overused in China at present， and to ensure the national food security of China at macro level. Methods employed in the paper include economic analysis， literature summary and empirical research. The results indicated that disorderly use of land was the result of rational choice of individual farmers according to the methods of economic analysis， literature summary and empirical research， and fallow system was beneficial to interests of the country and farmers. Thus， three implementation patterns of fallow system were designed including seasonal fallow model， fallow model based on land transfer and macro\|planned fallow model．

Key words: fallow system, abandoned land, food security