Several studies have attempted to test students' misconceptions of physics and to provide teaching strategies in order to repair them. The results from these studies have revealed that the diagnosis of students' misconception is crucial, although they often failed to grasp the practice of its implementation. In terms of being a type of methodology for science education, the Internet allows large-scale surveys and investigations to be carried out in a relatively short period of time. This paper reports the results of the development, implementation, and evaluation of a WEb-based SYStem for TEsting students' Misconceptions in physics (WEBSYSTEM) aimed at three groups (science educational researchers who study students' physics conceptions using the system as a detector, school science teachers who practice it as an instructional material, and students who benefit from it for their self-directed learning). The web-based testing system is based on a review of the instructional development strategies of ADDIE (Gustafson, Branch, 2002; Rha, Chung, 2001). Results showed that WEBSYSTEM could work effectively as a multi-purposed tool for the three target groups with a further partial revision, providing educational researchers with resourceful data to study students' misconceptions in physics. Issues of administrative strategies, reexamination of questionnaires, and international collaboration via WEBSYSTEM are discussed.