Due to the continuous rainfall, concentrated rainstorm, earthquake and so on caused by the rainy season and typhoon, the accidents caused by falling stone from hillside to road occur frequently. From these accidents, the opportunity to devote to the cause of falling stone countermeasures is improving. In the cause of falling stone countermeasures, road disaster prevention inspection and field investigation play a very important role. Selection of the survey areas and conduction the field survey is important on the project of falling rock measures. However, it is concerned that oversight of falling rock sources and waste of time at field survey, because of the diagram that cannot express the earth surface correctly. Also, it is difficult to express all data in a diagram made by aerial laser surveying although it is good at expression of the earth surface properly. So, we made micro topography highlight map to express the change in terrain finely and emphasize the steep cliff by combining diagrams. In this study, we extracted falling rock source on the desk and survey the selected area by micro topography highlight map. In addition, we verify its result by point cloud data. As a result, we report that we were able to extract steep cliffs of 1.4 m or more in height and 60° or more in terms of angle.