A gate driver includes: a drive circuit configured to drive, in accordance with an input signal that commands to turn on/off a switching element connected between high and low power supply potential parts, a gate of the switching element; a time storage circuit configured to store a time length from when the input signal is switched to an on command to when a recovery surge voltage generated by a diode that is opposite to the switching element is detected; a switching determination circuit configured to determine, in accordance with a detected value of a power supply voltage, whether to switch a gate driving condition; and a driving condition change circuit configured to change, in accordance with a determination result of the switching determination circuit, the gate driving condition at a time of current turn-on by the time length stored at a time of previous turn-on.