Currently, the fruit industry developed rapidly and brought a good deal of waste. It would pollute the ecological environment, cause economic losses, and harm human health due to improper handling. Therefore, this study investigated the effect of different inoculation ratios on methane production by anaerobic digestion (AD) of fruit waste. The results showed that the AD system at the inoculation ratio of 1:2 performed the best result, which achieved the highest methane production at 8280 mL. Besides, this system also demonstrated superior stability. The concentrations of NH4+-N and alkalinity were higher than other groups, which indicated a more stable AD process. These results indicated that the appropriate inoculation ratio played a crucial role in the efficiency and stability of the AD process. This study provided a positive promotion for the application and optimization of technology.