Abstract: The study was aimed to study the effects of corn flour and king grass at different supplement dosage on fermentation quality of tropical Leucaena silage. The results showed that the Leucaena silage supplemented corn flour had better fermentation quality, which was similar to that of Leucaena control. Considering the quality of silage fermentation and actual production, the optimum supplement dosage of corn flour was 10% in Leucaena silage.