In the rollover protection system, the rollover body comprises two limbs which, with in each case one end, are pivotable in bearings arranged spaced apart transversely with respect to the vehicle, and which, by means of the other ends thereof which can be pivoted out, can be locked together in the protection position. To increase the support height and support breadth of a system of said type, it is proposed that one of the limbs is designed such that it can be telescopically lengthened. Said limb comprises the telescopic parts which, in the extended state, are locked, so as to be prevented from being retracted again, by means of a spring-loaded bolt in conjunction with a deployable locking element in the pushed-out position.