A constant temperature fermentation system was self-designed and used to study the relationships of gas production efficiency with time and temperature of digestion in anaerobic fermentation of Pineapple Leaf residue. Groups of experiments were conducted with total solids concentration (TS) being 20% and fermentation temperatures of four groups respectively being 25°C, 30°C, 35°C, and 40°C. Experiment results showed that the total gas yield of the group with 35°C was 662.8 L, which was much higher than gas yields of the other groups. The methane content of the group was 63.2%, almost the same with other groups. Multiple regression analysis was made with SAS software and the regression equation was set up. The optimum temperature, digestion time and maximum cumulative gas production of solids were 36.4°C, 55d, and 462.41mL/g respectively.