Abstract: Finger-joint quality is one of the key factors to the performance of wood products. The aim of this research was to evaluate the effect of end pressure on the quality of finger-joint of poplar and find the best end pressure by mechanical property test and microscopic analysis. The theoretical range of end pressure was firstly determined by examining load-displacement curves, and then five end pressure levels ranging from 3.0 MPa to 16.5 MPa were investigated based on the the theoretical range of end pressure. Test results showed that the end pressure did not affect on the modulus of elasticity. However, the effects on the modulus of rupture and tensile strength were significant. When the pressure was lower than critical pressure P_min, finger tip could not contact with finger root completely. Meanwhile, the crush and crack of joints increased markedly as the pressure exceeded 7.6 MPa. Both of the two situations were unable to obtain the best finger joint strength. It can be observed that the best end pressure for finger jointed poplar is about 7.0 MPa in this experiment, which is about 20% of the compressive strength of the material.