The education of interior design studio progressively integrated with spatial creativity, environmental solution, and natural and artificial sources can create human activities and architectural unique. Interior design students need to solve the design problems by the ways of project-based learning, and to promote the students individual discipline. Based on the characteristic of interior design studio, the studio procedure was developed and applied CPS series which Osborn and Parnes brought up this educational methodology including the steps of objective and mess finding, data finding, problem finding, idea finding, final solution finding. For understanding and evaluating the relationship of final solution finding with each step of CPS, we tried to establish a developed design method for individual student based on the method of grey relational analysis. This approach could be a new idea for interior design studio to promote the students’ capability of design creativity thinking.