Abstract: At present, the traditional exterior wall painting still adapted methods with brushing, roller painting and manual spraying. These methods had problems, such as low construction efficiency, uneven thickness control and high-altitude operation risks. This paper designed a large workspace exterior wall painting robot by cable-driven. The configuration of this painting robot adapted parallel-driven mode, which can realize four working modes, such as unrolling the paint roller, painting, reeling up the paint roller and moving. According to the traditional painting requirements and cable load conditions, a preliminary design scheme of this painting robot was carried out. The kinematic model was established. The motion trajectory planning was completed according to its working modes, and painting work sequence diagram was drawn to determine the collaborative working time of each task. The painting boundary conditions were set which combined working principle of this robot and the preliminary design scheme . With the help of simulation software, it was simulated and verified of trajectory planning. In addition, the painting task of one painting cycle was divided into five motion processes, and the correctness of five motion processes was verified by the length change law of four driven cables.