Abstract: An online matching and optimization method combining geometry and texture and a three-dimensional (3D) scanning system are provided. The method includes obtaining pairs of depth texture images with a one-to-one corresponding relationship, and collecting the pairs of the depth texture images including depth images by a depth sensor and collecting texture images by a camera device; adopting a strategy of coarse to fine to perform feature, matching on the depth texture images corresponding to a current frame and on the depth texture images corresponding to the target frames, to estimate a preliminary pose of the depth sensor in the 3D scanning system; combining a geometric constraint and a texture constraint to optimize the estimated preliminary pose, and obtaining a refined motion estimation between the frames.