This study proposes lighting simulation approach to assess lighting quality on motor ways and walk ways considering each type of form and growth of roadside trees. Simulation approach to assess quality of lighting is frequently used for lighting design which guarantees secure of drivers and pedestrians during the night time. But, road side trees which have diverse benefits for citizens acts on obstacles during night time needs lighting. The results of this study shows a possible way for tuning the aims of both lighting and road side tree. It will be possible to develop harmonic design standards for road way lighting if further study achieved based on the result of this study.