This research paper presents a knowledge-based system for creative design tools (CDT). The developed system provides designers with a creative design environment to enhance their design thinking. Several creative thinking tools and techniques are grouped, developed, and incorporated with various constructive knowledge databases which can widen the designer's knowledge and search skills in the process of design creation. CDT embodies: a user interface, five design modules, creativity tools, knowledge databases, and computer-aided design (CAD) tool. The main aim of the system is to enhance creative design thinking by providing various tools and constructive knowledge databases which can be expanded each time the designer uses the system. The system differs from conventional tools in that it is structured to incorporate creativity tools with knowledge databases needed by the designers in a user friendly environment. A case study is discussed and demonstrated to validate the proposed system.