The purpose of this research was to study the effect of mixing ratios of binder on the properties of leucaena (Leucaena leucocephala) pellets. In this study, the fermented cassava-rhizome was used as a binder in the production of leucaena (Leucaena leucocephala) pellets. The duration time of the fermentation process was three days. The mixing ratios of leucaena with fermented cassava-rhizome varied at 90:10, 80:20, 70:30, 60:40, and 50:50, respectively. The results demonstrated that the mixing ratios of binder affected the bulk density and durability of leucaena pellets. The increasing amount of fermented cassava-rhizome increased the bulk density and durability of leucaena pellets. The physical properties were determined following the Pellet Fuels Institute standard specification for residential/commercial densified fuel. Moreover, the results illustrated that the optimal mixing ratios (leucaena: fermented cassava-rhizome) in the production process of pellets was 70:30, as this mixing ratio provided the lowest energy consumption (420 kWh/ton) in pellets production and the highest mass yield at 94.3%. Thus, the results obtained from this research suggested that the fermented cassava-rhizome as a binder might be an alternative adhesive material for improving the asymmetrical structure and physical properties of biomass raw materials