The invention discloses a surface coloring device for hardware accessory machining. The surface coloring device comprises a machine frame, a first installation base, a first sliding assembly, a secondinstallation base, a transverse moving air cylinder, a second sliding assembly, a coloring box, a lifting air cylinder, a drying device and a machine box. The first installation base is arranged on the left side of the top of the machine frame, the first sliding assembly is arranged on the surface of the first installation base, the second installation base is arranged on the surface of the firstsliding assembly, the transverse moving air cylinder is arranged on the top of the second installation base, and the bottom of the second installation base is provided with the second sliding assembly. Since the transverse moving air cylinder, the lifting air cylinder and the drying device are arranged on equipment, when the coloring device carries on coloring on hardware accessories, a large number of labor resources are not needed, semi-automatic coloring is achieved, the enterprise production cost is reduced, enterprise economic benefits are improved, the coloring device is high in coloring efficiency, paint on the surfaces of the hardware accessories can be rapidly formed, and enterprise machining efficiency is improved.