A road paver includes a paving screed adjustable in height for installing a road surface layer and at least one holding device for carrying and positioning of at least one sensor unit. The holding device has at least one swivel arm module for fastening the holding device on the road paver, at least one carrier arm module and at least one sensor module comprising the sensor unit. The carrier arm module is fastened by a first clamping device on the swivel arm module and the sensor module is fastened by a second clamping device on the carrier arm module, wherein the first and the second clamping device are formed respectively for a predetermined clamping force when the respective clamping devices are in a closed position.