Longitudinal force control apparatus and saddled or straddle type vehicle having the same

Provided is a longitudinal force control apparatus (31). A lateral acceleration acquisition section (34) acquires a lateral acceleration along a right-left direction acting on a vehicle. A bank angle acquisition section (46) acquires a bank angle of the vehicle. A longitudinal force control section (32) may decrease an absolute value of a longitudinal force at least with respect to a driving wheel of the vehicle based on the acquired lateral acceleration and the bank angle when it is determined that a calculated lateral-skid acceleration is equal to or greater than a predetermined threshold. The longitudinal force is a sum of forces along a front-rear direction acting on the driving wheel.