As a creative activity with a particular purpose, design needs to define and solve problems. The rationalization of a series of decisions, from problem definition to solution, invariably depends on the guidance and support of design logic. Accordingly, this study proposed the triple design logic system of deduction, configuration, and narration based on complete comprehension of the essence of three stages in the design process: conceptualization, form generation, and design expression. The logic of deduction structured a path from problem definition to solution, responding to the site’s functional requirements and conceptual qualities and generating ambiguous spatial organization. Subsequently, the logic of configuration deepened this ambiguous space and further implemented it into concrete form. As a means of design expression, the logic of narration reverted to the previous demonstrations of the design problems and solutions, achieving the reorganization and efficient transmission of information. In addition, four design projects were selected as examples to verify the universality of the design logic system and to enhance its application in future practice.