D-bale knotter is one of the key parts of square baler, which influences the efficiency and quality of baler. Based on reverse engineering, D-bale knotter was reconstituted and the accuracy of working surfaces was analyzed. The results showed that more than 90% domain for all the working surfaces can achieve the precise level above. Reconstruction parts of D-bale knotter were assembled and then simulated by using the software Solidworks. The angular velocity and displacement data of twine holder, bill hook, wiping arm, and driving dentate disc were obtained and the movement relationships of these parts were further analyzed. This study will provide basic data for the optimization of D-bale knotter.