Abstract: The total press time can be shortened greatly and some properties of boards can be improved with the technique of steam injection vacuum pressing(SIVP).This new technique would be one of directions of wood composites pressing.This paper focused on SIVP for aqueous PF resin bonded poplar flake board,choosing vapor pressure,steam injection time,steam hold time,and vacuum time as four main factors in experiments.The quadratic mathematical model and Dn optimal method were used to assign the experimental plan.PF resin bonded flake boards were produced with the experimental unsealed steam injection vacuum press,BY602×4.The regression equations were developed and then optimized SIVP technology factors.The deviation of regression equations was little enough to predict the property of boards.