Recently, apartment housing in the total housing types exceeds 50%, and the construction of apartment housing has been encouraging the high-rise and heavily-densed urban residential areas. Based on judicial precedents, in order to acquire the sunshine access right in residential areas, duration of sunshine access should be secured more than two consecutive hours in six hours from 09:00 to 15:00 at the winter solstice, or at least four hours in eight hours from 08:00 to 16:00 at the winter solstice. However, the cases that duration of sunshine access requirements cannot be met in an overcrowded area occur, and accordingly disputes between adjoining buildings in relation to the violation of sunshine access right and view right have been increasing. The sunshine access evaluation is the method to measure sunshine access time in disputed areas, but there are plenty of difficulties and restrictions in determining sunshine access time just once a year, which is the winter solstice. Therefore, a judicial trial uses 3D simulations as a computation method of sunshine access time to measure the degree of sunshine access violation, makes reports, and uses them as judgment data. However, there can be errors in the evaluation due to the degrees of accuracy in input data such as building shapes, distance between buildings, and level of building sites, and the characteristics of simulation programs. Therefore, the simulation methodology for evaluating sunshine access right of apartment housing by Autodesk VIZ 2006 and a self-developed VIEW Program was developed. The validity of the simulation results by comparing with real measurement of apartment housing was verified.