In an outboard motor tilt movement interruption device, when a tilt-up stop condition is established by a presence of an obstacle in a tilt-up movement range of an outboard motor and the obstacle and the outboard motor are equal to or less than a predetermined distance from each other, a circuit arranged to actuate a tilt device is cut off by an ON/OFF switch. On the other hand, when the tilt-up stop condition is not established, the circuit is connected. When the tilt-up stop condition is established during an operation of the ON/OFF switch, the circuit is cut off, and tilt-up of the outboard motor is stopped. Thereafter, when the tilt-up stop condition becomes canceled, the circuit is connected and tilt-up of the outboard motor is restarted.