Abstract: The documents collected from the Poyang Lake Region by Shanghai Jiao Tong University record a dispute between the Cao Clan based in Duchang county and Yang Clan based in Poyang county during the Qing dynasty. From 1776 to 1799，the two clans constantly disputed over the ownership of three lakes， which were located along the board of the two counties，and they even brought the case to Beijing. According to our study，however, the claimant，Cao clan had no legitimate claim over the disputed lakes. Even though the Cao clan depicted themselves as the victim，but in fact，they were trying to appropriate Yang clan’s property. This case shows that the civil justice of the Qing dynasty was committed to protect the property rights of the commoners;due to the protection of the state，the Cao clan，which was stronger，admitted the rights of the Yang clan，which was weaker. More importantly，the state was creative in solving the dispute:it firstly judged the rights and wrongs based on evidence，and then introduced market mechanism to achieve a win-win result. This approach was more effective in solving civil disputes than solely relying on law.

摘要： 上海交通大学收集的鄱阳湖区民间文书,记录了清代中期江西都昌县曹氏与鄱阳县杨氏之间的一桩官司。两姓就两县交界处三片湖面的产权,从乾隆四十一年(1776)一直争讼到嘉庆四年(1799),从鄱阳湖一路打官司到北京城。通过对相关58件文书的分析,结合其他材料,我们发现:虽然原告方曹姓将自己描绘为受害者,但实际上对争议湖产不具有充分的产权依据,是利用各种借口来侵占杨姓湖产。这个案例表明,清代民事司法具有积极保护民人产权的一面:正是官方对民人产权的保护,才迫使强势的曹家承认弱势的杨姓的产权。更重要的是,官方对这个纠纷的解决颇有创意:先根据证据判明是非,认定权益归属,然后引入市场机制,促使双方达成双赢的共识。这种法律与市场的双管齐下,比仅仅依法判定是非,更能抓住产权纠纷的根本。