The present disclosure relates to a method and device for sending a control protocol data unit (PDU) and belongs to the field of communication technologies. The method comprises: establishing a dedicated bearer for transporting a control PDU; when a control PDU to be sent exists, sending, on a logical channel to which the dedicated bearer corresponds, the control PDU to a media access control (MAC) entity of the communication device through a radio link control (RLC) entity of the communication device; and sending the control PDU through the MAC entity according to a promoted priority of the logical channel. The present disclosure can shorten the sending delay of the control PDU.