The purpose of this study is to investigate alteration situation and user demand through the case study, to analyze the problems of the user participatory design, and to propose the improvement direction of user participation in the apartment housing. The results of this study are as follows: 1) The method of participatory design using a questionary must be improved with other communication methods between suppliers and users to adapt to the demands of users. 2) The range of menu and the time of participation must be varied to select various materials, colors, types of the interior finish and floor plan freely according to users. 3) Users have the positive attitude about the menu-option method and want to other methods of participatory design like the flexible housing method.