A vehicle side underrun protection having at least one load-bearing member that extends between the wheels or sets of wheels of the vehicle in the vehicle's longitudinal direction. The member(s) extend basically along the outer contour of the vehicle and serves as side impact protection and/or protection to prevent unprotected road-users ending up under the vehicle. The side underrun protection (1) has at least one longitudinal section (12, 13, 14) suspended in at least two first brackets (2, 3) fixed to the vehicle, along which brackets (2, 3) at least one end of each individual section (12, 13, 14) of the side underrun protection (1) is vertically adjustable from at least a first, active position to a second, inactive position. The invention also relates to a vehicle provided with such a side underrun protection.