This invention concerns a remote control unmanned boat which can be freely operated by remote control and a remote control device. The remote control unmanned boat comprises a propelling power source 11 for generating a propelling power, a steering device 13 for freely varying the direction of advance, a first transmit-receive antenna 24 for receiving the signal transmitted by ratio from a control device 20, a first controller 15 for controlling the propelling power source 11 and the steering device 13 based on the signal received from the first transmit-receive antenna 14, a memory device 17 for memorizing the initial position set in advance, and a GPS antenna 16 for receiving the electric wave transmitted from an artificial satellite. The first controller 15 calculates the present position based on the electric wave received by the GPS antenna 16 and, when the stated condition is satisfied, initiates automatic control of the propelling power source 11 and the steering device 13 so as to attain regression to the initial position based on the present position and the initial position. Thus, the remote control unmanned boat has no possibility of being missed.