The invention discloses a transmission device based on short wave communication. The transmission device comprises a wired fax transceiver and a short wave fax transceiver. The wired fax transceiver comprises a PSTN user interface circuit and an Ethernet interface, the PSTN user interface circuit is connected with a modem, a DTMF signal receiver and an analog signal processing, the Ethernet interface, the modem and the DTMF signal receiver are connected with a first ARM single chip microcomputer, the short wave fax transceiver comprises a short wave radio, the short wave radio is connected with a short wave modem and an analog signal access circuit, the short wave modem is connected with a second ARM single chip microcomputer, the analog signal access circuit is connected with an analog signal processing circuit, the short wave fax transceiver further comprises an Ethernet concentrator connected with the Ethernet interface, and the short wave radio is also connected with a short wave antenna. Under the condition of not changing the ordinary fax machine, faxes are received and sent and computer data communication and voice calls are achieved by means of the short wave communicationmode. The invention further discloses a signal transmission method using the device.