In residential street planning, it is very important to examine how to deal with parking vehicles on residential streets, because pedestrian traffic usually competes with parking vehicles, and pedestrians are often faced with dangerous situation. Carring out several investigations, this research describes some different aspects of parking problems in residential areas. This research clarifies that a lot of parking vehicles are dangerous to residents, but there are some permissible number of parking spaces located on streets, since they have few effects on safety of residential streets. Also this study calculates parking demand for visitors to a street, which can be treated on the on-street spaces.