Technical Abstract: Rice bran, a by-product of rice milling, is mainly used as animal feed with low economic value. It is desirable to develop new applications through processing to increase its value. In this study, rice bran was chemically and thermally modified by using alkaline and heat to develop its adhesive property. The rice bran was modified at pH 12 and temperature 100°C. The characteristics of rice straw-based particleboard bound with a combination of rice bran based-adhesive and PMDI (polymeric diphenylmethane diisocyanate) were evaluated. The evaluated properties of the particleboard included modulus of rupture (MOR), modulus of elasticity (MOE), water absorption and thickness swell. Results showed that up to 30% PMDI may be replaced with rice bran-based adhesive to obtain quality products with performance characteristics similar to those of PMDI-bound particleboard. The use of the developed bio-based adhesive should be an environmentally friendly alternative to synthetic particleboard adhesives that may reduce dependency on petroleum and its derivatives.