With wheat straw and wood chips as raw materials, three-layer particleboard was made with Mg-based inorganic adhesive. Effects of wheat straw/wood ratio, board density, hot-pressing time and temperature on physical and mechanical properties of the board samples were studied. Results showed that modulus of rupture（MOR）, modulus of elasticity（MOE） and thickness swelling（TS） gradually decreased and internal bond strength（IB） gradually increased with increasing the wheat straw in the wheat straw/wood ratio. As board density increased and hot-pressing time extended, MOR, MOE and IB gradually increased while TS decreased. As hot-pressing temperature raised, MOR, MOE and IB first gradually increased and then decreased, TS was in contrast. The optimal preparation parameters were:wheat straw-wood mass ratio of 5 : 5, board density of 1.2 g/cm,3, hot-pressing time of 30 min and hot-pressing temperature of 100 ℃.