Rice straw, whose outer surface is covered by silica, has relative higher ash content. 100% pure rice straw panel board manufactured with conventional low cost urea formaldehyde (UF) was featured by low strength, poor dimensional stability and high resin requirement. This work employed liquid hot water to pretreat rice straw, with pretreatment temperature of 160℃ and 170℃ and residence time of 2min, 4min and 6min. The pretreated rice straw was mixed with wood particle at the ratio of 1∶1 by using UF to produce rice straw-wood composite with 0.75g/cm3 density. The hot press temperature and pressure were 150℃ and 3.5MPa, respectively. The resin application level was 12%. The experimental results indicated that the panel board made with rice straw pretreated under 160℃ for 6min and 170℃ for 4min and 6min met the requirement of China national standard for particleboard GB/T 4897—2003.