We discuss the possibility of measuring the height of single tree in broadleaved forest by application of airborne laser scanner system operated for surveying large target area by a low density of footprint. The airborne laser scanner system is applied for obtaining Digital Surface Model (DSM) and Digital Terrain Model (DTM) in many studies. The cost of operating this system and the time that hangs to processing of the data, however, increase as the target area expands. We operated the system to obtain first and last pulse return elevation data of entire target area by a low density of footprint, and created Digital Canopy Height Model (DCHM). Using the data, we extracted highest amount of DCHM at each single tree area The actual tree height was gained to correct the height using one route data which has high density of footprint. In the process DCHM data were sliced for some segments at each height level, and the highest height on single tree canopy was extracted while referring it. We compared highest amount of DCHM at each single tree area in low density data and actual tree height, after the result the conversion formula was gained. This conversion formula can be adapted to all of the data, and we can get tree height distribution map at the entire target region. Using this data, we can estimate biomass of the broadleaved forest and forest inventory database about the target region can be updated.