Pinus massoniana is one of the most important species in plantation-grown forest in China and been widely used in many fields. However, the properties of strong moisture absorption and weak dimensional stability limit its development. The introduction of thermal treatment and carbonization has repaired this defect in certain extent but at the cost of high energy-consumption. In this paper, whole factor analysis method was used to find a novel and optimized process parameter, the results show as follows: The temperature and relative humidity is remarkable to the moisture content influence; the time and skim the liquid fraction are remarkable to the moisture content influence at 0.1 level. (2) According to skim wood moisture content changes, the better to determine degreasing process as follows: temperature of 135degC, pressure of 0.4 MPa, time of 6.5 h, skim the liquid fraction is 9.5%.