A composite coating apparatus includes a main body, two carrying boards, and two actuators. The main body defines a first chamber and a second chamber with a separating board intervening therebetween. The separating board defines a coating opening intercommunicating with the chambers. The carrying boards are received in the first chamber and rotatably connected to the separating board at two sides of the coating opening. Each carrying board defines a receiving groove for holding a substrate. The actuators are configured for driving the carrying boards to rotate between a first coating position, in which the substrate is exposed to the second chamber for a first coating process carried out in the second chamber via the coating opening, and a second coating position, in which the substrate faces away from the separating board for a second coating process carried out in the first chamber.