A circuit for detecting a leakage current in a semiconductor element includes a setting circuit and a detector. The semiconductor element includes a first terminal at a high-potential-side of the semiconductor element, a second terminal at a low-potential-side of the semiconductor element, and a control terminal. The control terminal receives a signal for controlling a conduction state between the first terminal and the second terminal. The setting circuit sets a duration during which a charging current flows to the control terminal as an undetectable duration, in response to turning on the semiconductor element. The detector outputs a detected signal based on a condition that the leakage current flowing from the control terminal to the second terminal, after the undetectable duration has been elapsed.