The strain rate effect of timber should be taken into account in the detailed analysis of timber structure during earthquakes. In order to investigate the impact of seismic strain rate on the mechanical properties of timber under uniaxial compression， two types of timber， Larix and Pinus Sylvestris， were selected， and perpendicular-to-grain and parallel-to-grain specimens were designed for each type. The stress-strain relationship， failure mode， elastic modulus， and compressive strength of the timber were investigated through uniaxial compression tests under seismic strain rates of 10-3 s-1， 10-2 s-1， 10-1 s-1， as well as a quasi-static strain rate of 10-4 s-1. The results indicated a noticeable seismic strain rate effect on the compressive strength and elastic modulus of timber under uniaxial compression. As the seismic strain rate increased， the compressive strength of timber exhibited a more significant increase. The uniaxial compression constitutive model was established， taking into account the seismic strain rate effect. Additionally， a corresponding UMAT subroutine was programmed and integrated into the ABAQUS finite element software. The numerical simulation of timber under uniaxial compression was performed. The results exhibited a strong agreement with the experimental findings， thereby validating the accuracy of both the constitutive model and UMAT subroutine. The research findings can offer constitutive support for seismic analysis of timber structures.