A communication device used in a garbage incineration system comprises a cylinder body. The upper end of the cylinder body is provided with a second connection opening for being connected with a second incineration system chamber. The lower end of the cylinder body is provided with a third connection opening for being connected with a vertical furnace. The side wall of the cylinder body is provided with a first connection opening for being connected with a kiln tail of a rotary kiln. The side wall of the cylinder body is further provided with an observation opening and an overhauling opening. The second connection opening is provided with a connection cylinder. The inner wall of the connection cylinder is sequentially provided with a light insulation castable layer and a refractory brick layer from outside to inside. A first flange is arranged on the outer end face of the connection cylinder. A circular-truncated-cone-shaped connector is arranged on the third connection opening. The inner wall of the circular-truncated-cone-shaped connector is provided with a refractory castable layer. The first connection opening is provided with a mounting cylinder. The outer end face of the mounting cylinder is provided with a rotary kiln sealing plate. The inner wall of the mounting cylinder is provided with a refractory castable layer. The communication device is reasonable in design and is safe and reliable under the high-temperature condition, and the service life of the connected rotary kiln, the second incineration system chamber and the vertical furnace is prolonged effectively.