Abstract: Masson Pine (Pinus massoniana Lamb.) is a timber species growing quickly and widely in southern China. But its wood is easily deteriorated by termites and various decaying fungi, and becomes warping easily when seasoning. This wood has hardly been made full-use of up to now.This paper discusses the reason why warping occures so commonly in this wood and illustrates the use of rosin as a constituent of waterrepellent preservative. A simple treating process was suggested and a preliminary trial proved successful.