An operational condition of an outboard motor 1 is detected by an ECU 29, and transmitted via a communication unit 228, from a communication apparatus 283 to a base station 30. Antennas 32 and a cable 33 are arranged along an inner surface of an engine cover 12. The cable 33 is provided with a connector 34 for connecting the antenna 32 to a communication unit 28 and a GPS receiving circuit 31. The communication apparatus and the antennas are held floating in a case 351 which is filled with a gel, and the case 351 is fixed to the engine cover 12. A communication unit 28 is provided inside an engine cover 12. A housing portion 41 for a portable phone PH is provided pivoted about the cover 12 in such a manner that the portable phone is removable from the housing portion 41.