Abstract:This report is concerned with the strength of bolted joints in which the members were made from the Korean Pine timbers (Pinus koraiensis Sieb. Et Zucc.). The specimens are three-member joints with single bolt in double shear. The load was applied parallel to the grain of the wood. All the joints were tested in compression. The bolts in the bolted-test specimens were without washers and nuts. According to the size of the diameter of bolts, the specimens were divided into five groups. In each group, the thickness of the inner members equals to 50 mm, but the thickness of the outer members is varied. This experimental work described includes tests to compare the strength of joints with five different ratio of thickness of the inner and outer members. The relations between load and thickness of members, and between bearing strength of bolt-hole and crushing strength of wood were examined respectively. The factor of safety of the bolted joints was obtained by comparison with the tested load to the safe working load which was counted according to Soviet‘s Specifications HиTy-122-55 and HиTy-2-47 respectively. Based upon the analysis of factor of safety, the authors conclude that the empirical equations which used to calculate the safe working load of the bolted joints according to HиTy-2-47 are properly to satisfy the engineering purposes on strength and stiffness.