To provide a load protection circuit that is adapted to protect negative-polarity voltage from being applied on loads that operates on a direct-current, and to minimize a loss when a voltage is being supplied at a normal polarity.

A semiconductor channel formed between input/output terminals of a FETQ1 is inserted and connected to either one of a pair of positive and negative electric power lines that supply voltages to a load L, a negative-polarity diode Di is connected between an input terminal and an output terminal of the FETQ1. Such a voltage is designed to be applied on the gate terminal of the FETQ1 that brings the semiconductor channel into an energized state when a voltage with the predetermined polarity is applied on the input terminal, and brings the semiconductor channel into an interrupted state when a voltage with a negative polarity is applied on the input terminal.