Disclosed herein is a shoulder collapse risk monitoring system capable of alerting a driver to a risk of a road shoulder collapse during approach operations to the shoulder.The system includes: a shoulder shape measuring device 101 that measures a shape and slope angle of a road shoulder around a vehicle; a measurement position identification section 121 that identifies a wheel position relative to the shoulder when the shape and slope angle of the shoulder are measured by the shoulder shape measuring device; a shoulder strength calculating section 122 that calculates, from the shape and slope angle of the shoulder measured by the shoulder shape measuring device, strength of the shoulder at the wheel position identified by the measurement position identification section; a wheel load measuring section 123 that measures a wheel load of the wheel whose position has been identified by the measurement position identification section; and an alert device 105 that presents information on a risk of a collapse of the shoulder at the identified wheel position by comparing the wheel load measured by the wheel load measuring section, with the shoulder strength calculated by the shoulder strength calculating section.