Industrial vehicle and alarm system in industrial vehicle

Provided is an alarm system (1) in a forklift (2) comprising: an alarm transmitter device (10) mounted in a vehicle body (20); and an alarm (3) that detects alarm signals from the alarm transmitter device (10) and becomes aware of the approach of the forklift (2). The alarm transmitter device (10) has: an oscillation coil (11) that generates magnetic flux as an alarm signal, by electromagnetic induction; and a control unit (14) that changes the magnetic flux density from the oscillation coil (11) according to running speed and operation at departure and controls the range that alarm signals can be detected by the alarm (3). The alarm (3) has: a detection coil (31) that generates an induced current from the magnetic flux of the oscillation coil (11); a detection unit (32) that decides whether or not the induced current is at or above a prescribed value; and a buzzer (33) that operates if the detection unit (32) decides that the induced current is at or above the prescribed value.