The orthogonal theories were carried out to analyze the effect of MDI, UF and FRW content on the mechanical and fire retardant properties of rice-straw based boards in this paper. The interface alkaline treatment showed a significant effect on the surface bonding performance of rice- straw. The bonding property of rice-straw based boards increased with the increasing of resin content, especially for the effect of MDI content on MOR, MOE. The tendency of pkHRR decreased and the target for fire retardant realized by the FRW content increased. Based on analysis, the optimal technical parameters were obtained as MDI content 3%, UF content 6% and FRW fire retardant 10% separately.