The purpose of this study is to analyze the characteristics of Mario Botta's residential design. The characteristics of Mario Botta's residential design are following as : 1. The residential design of Mario Botta planed from 1960' to 1970's is based on the style composition method of modern design, specially by the influence of Le Corbusier and Louis I. Kahn. Botta's residential design of the 1980's is generally affected by A. Palladio, and is characterized as the representation of classic standard. The residential design of the 1980's shows the establishment level of Mario Botta's residential design, and produces particular Botta's facade. 2. The characteristics of Mario Botta's spatial composition on residential design could be implicated by the spatial distribution of each floor which is divided by three floors, simple and primitive volume which has a symmetry, opening through the massive elimination n the center of front, double skin, the contrast between void and solid, and the inflow of light through the top-light. 3. Most Botta's residential designs have Loggia in the center of facade working as a buffer space which joins outside and inside space together. They also lead the spatial continuous flow. The inside space is combined by the light coming through top-light and vertical opening. 4. They have high accomplishment in complicating details. They show the outside design of a horizontal belt according to the module of concrete block and the decorated design using compositional materials such as an unevenness piled up askew concrete block .