A system for monitoring the levelness of a multi-wing agricultural implement may include a central frame section, a wing section pivotably coupled to the central frame section and a field contour sensor configured to generate data indicative of a contour of an aft portion of the field located rearward of the implement relative to a direction of travel of the implement. The system may further include a controller communicatively coupled to the field contour sensor. The controller may be configured to monitor the data received from the field contour sensor and assess a levelness of the implement based at least in part on the contour of the aft portion of the field.