This paper addresses the autonomous landing of an unmanned aerial vehicle (UAV) on a ground vehicle. Unlike most of the previous research on autonomous UAV landing that used onboard sensors mounted on the UAV, this study suggests using a lidar mounted on a ground vehicle for lidar-guided landing. To estimate the relative position of the UAV with respect to the landing platform, a clustering algorithm is applied. In addition, to enhance the safety of landing, a decision making procedure based on simple reachability analysis is introduced. The proposed landing method is implemented and then verified through an experiment.