A parking assist device assists entry or exit of a vehicle with respect to a parking space through an automatic control of a steering device. The parking assist device includes: a calculator that obtains, to perform the automatic control of the steering device, a path for allowing the vehicle to enter or exit the parking space based on the parking space, calculates an amount of temperature rise of the steering device at the execution of the automatic control for allowing the vehicle to move along the obtained path, and calculates a predicted temperature of the steering device at the execution of the automatic control by adding the calculated amount of temperature rise to a current value of the temperature of the steering device; and a controller that inhibits the execution of the automatic control when the predicted temperature is equal to or higher than a determination value.