PARKING ASSISTANCE DEVICE AND PARKING ASSISTANCE METHOD

In a parking assistance device, a target parking position calculation unit calculates a target parking position of a subject vehicle based on a position of a corner point of a parking space. A constraint condition setting unit sets a constraint condition regarding a target parking route for guiding the subject vehicle to the target parking position based on a position and a posture angle of the subject vehicle, peripheral information of the subject vehicle, and the position of the corner point of the parking space. The constraint condition includes a condition that a curvature change rate of the target parking route is continuous. A target parking route calculation unit calculates the target parking route based on the position and the posture angle of the subject vehicle, the position of the corner point of the parking space, the target parking position, and the constraint condition.