The aim of this study was to determine the performance of three-layer particleboard made from wheat straw and veneer splinters, as waste materials. For the purpose of evaluation, compositions of wheat straw and beech veneer splinters at different mixture rates were compared for some of properties. Physical (thickness swelling and water absorption) and mechanical properties (modulus of rupture, modulus of elasticity, internal bond and impact strength) of the boards were evaluated. Effects of mixing ratios of fibrous material and press temperature on the above-mentioned properties were also investigated. The mixing ratios of beech veneer with wheat straw were 100%:0%, 75%:25%, 50%:50%, 25%:75% and 0%:100%, respectively. A commercial urea- formaldehyde (UF) adhesive was used as binder. A total of 10 experimental boards with an average target density of 0.70 g cm3 across all mixtures were fabricated. All the mechanical and physical properties of the boards were improved when the press temperature was increased from 140 to 170 C. Analysis of data revealed that the mechanical properties were significantly different among the board types. With the exception of modulus of elasticity, the other properties were decreased by the addition of wheat straw particles. In general, water absorption and thickness swelling decreased with the increase of wheat straw content. The presence of wheat straw in the particleboards resulted in higher water absorption and thickness swelling. Finally, it can be stated that wheat straw and beech veneer splinters have potential as supplement fibrous materials, in combination with wood particles for particleboard manufacturing and indoor applications.