The present study is about a 3-dimensional design method based on prototype model using the parametric technique. Until now, architecture design using the computer has been limited to the 2-dimensional level. Although the outputs of some modeling programs appear 3-dimensional, they are basically the outcomes of 2-dimensional perspective drawings or presentations and, in the true sense, cannot be 3-dimensional methods using all variables related to three dimensions. To overcome the limitations and to apply the computer to design in a more useful way, machinery, automobile, aviation and shipbuilding industries have developed 3-dimensional tools based on concepts such as object-oriented modeling technique and parametric technique. However, few of such attempts have been made in the area of architecture. Thus, viewing that, among several methods tried in other industries, the 3-dimensional design technology based on the parametric technique may be usable in architecture design, the present study purposed to examine how to introduce and apply the concept to architecture design. With this purpose, finding the possibility of applying together the object-oriented modeling and the parametric modeling method, which are 3-dimensional modeling methods, and the design prototype method and the previous case based design method, which are design methods，we examined a 3-dimensional architecture design method under the title 'Prototype-based Design Method Using Parametric Technique’ and assessed its possibility by applying the method to real cases experimentally.