A fast digital measurement method of cross-laminated timber wood failure percentage based on grayscale and color image processing was proposed. To verify the feasibility of this method， the shear failure samples prepared with larch and carbonized bamboo as the base material and phenolic resin and isocyanic acid as the adhesives were tested under dry and wet shear conditions. The results show that the wood failure percentage calculated by the gray-scale and color image processing methods are in good agreement with the experimental values， and the errors meet the requirements of engineering applications. However， the color change of the wood damage level and the wood failure percentage image have a greater impact on the measurement accuracy. Among them， the change of the inherent color of the adhesive has a greater impact on the accuracy of the threshold segmentation gray-scale wood failure percentage image measurement method， while the environmental impact is the main factor of the color wood failure percentage measurement method of pixel statistics.