曹魏以邓艾为代表蓄水兴屯，西晋以杜预为代表毁陂废屯，南北朝以筑浮山堰为代表以水代兵，是淮河水利史上的三件大事。学者常把曹魏两淮屯田，两晋江淮庄园经济，作为这一时期农业发展的论据。本文着重探寻这一时期两淮农业兴衰变化的原因，剖析曹魏蓄水屯田的背景、作用及其片面性；西晋毁陂废屯对促进农业生产的积极意义；浮山堰对农业的严重破坏。 Wei Wei to Deng Ai as the representative of the reservoir Xing Tun, the Western Jin dynasty as the predestination Destroyed Tuen, the Northern and Southern Dynasties as built on behalf of the Fushan Weir, is the history of the Huaihe River in the three major events. Scholars often Cao Wei Huai Tuntian, Jinjiang JAC manor economy, as an argument for the development of agriculture during this period. This article focuses on exploring the reasons for the rise and fall of agriculture in Huaihe and Huaihua during this period, analyzing the background, function and unilateralism of Caoweizhui farmland; the positive significance of destruction of wasteland in Western Jin Dynasty to promote agricultural production; and serious damage to agriculture by Fushan weir.