It laid the institutional foundation for the development of modern agricultural economy, showed strong vitality and greatly promoted the development of rural economy. However, with the further development of rural economy, the adjustment of agricultural production structure, agricultural industrialization and large-scale operation, and China's accession to WTO, the single family management of land can no longer meet the requirements of rural economic development. Therefore, in order to improve labor productivity and land productivity and realize large-scale and specialized production, it is necessary to establish a legal and reasonable land transfer mechanism, because the operation of a single farmer cannot achieve economies of scale. Scale economy is the concept of enterprise economy and industrial economy, which basically means: due to the improvement of production specialization level and other reasons, the unit cost of enterprises decreases, thus forming an economy in which the long-term average cost of enterprises decreases with the increase of output. There are many people who study the two aspects of this paper (scale economy and agricultural land system reform in China), but few people study together and there are many innovations. If we study them together, my humble opinion is that the requirement of scale economy will accelerate the reform of agricultural land system and land circulation in China.