A coating device includes a main body, a transport device, at least one loader, a driving device. The main body has a top plate, a bottom plate, and a pair of sidewalls connecting the top plate and bottom plate. The sidewalls respectively define an input gate and an output gate. The transport device includes a transport track passing through the input gate and the output gate, and at least one lifting arm mounted on the transport track. Each loader is configured for loading workpieces and includes a rotary shaft, at least one loading frame rotatably connected with the rotary shaft. The driving device is mounted on the top plate. Each lifting arm is configured for clamping a corresponding loader and transporting the corresponding loader to engage with the driving device. The driving device rotates the corresponding loader rotary shaft through the rotary shaft of the corresponding loader.