Abstract: In order to reduce the biogas slurry and heat loss from the wet anaerobic fermentation process of continuous feeding,the effect of long-term reflux biogas slurry on the anaerobic fermentation of cow manure was studied in a 50 L continuous feed wet anaerobic fermentation plant. At the mesophile temperature（37±1）℃,the daily gas production,methane volume fraction,pH value,SCOD content and ammonia nitrogen content of biogas liquid reflux ratios（0%,30%,40%,50%,60%）were studied. And the mechanism of promoting the methane recovery is researched by kinetic analysis. The results show that the gas production in the test group with a reflux ratio of 40% gradually increases during the reflux phase and stabilizes after 108 days. The highest daily gas production during the test period is 62.45 L,and the volumetric gas production rate is 1.39 L/L. Compared with the test group with a reflux ratio of 0% and 30%,it is increased by 25.46% and 9.22% respectively. The test group with a reflux ratio of 50% and 60% achieves a maximum daily gas production of 62.29 L and 62.40 L in the reflux phase,but the daily gas production begin to decrease at the 95 th and 78 th day respectively,and at the end of the 120 d test,it is already below the test group with a reflux ratio of 40%. Finally,the theoretical calculation of the increase of the fermentation feed temperature by the reflux biogas slurry shows that the reflux biogas slurry can reduce the energy consumption of the fermentation raw material by 27.23% to 33.38%.