In order to keep up with the coming information era, it is an urgent task for medical institutes to integrate information technology into health education. The purpose of this study is to apply transtheoretical model, situated problem-based learning strategy, the ARCS motivation model and e-learning environment to design and develop on-line healthy weight reduction curriculum and website for adolescent.The Healthy Weight Reduction Curriculum was designed and provided for its mission accordingly. The curriculum proposed is a hybrid of on-line and face-to-face styles. This study mapped out ten units in the web site to introduce healthy weight reduction program to high schoolstudents. These units include: (1) school history building, (2)health care center, (3)restaurant, (4)welfare society, (5)the sports ground, (6)bulletin board system (BBS) for postings, (7)the bulletin board, (8)internet Resources, (9) my diary, and (10) contacting with us. When designing the curriculum, the factors were considered as in the following: (1) anonymity help to reduce the embarrassment of face-to-face situations, (2) high interactivity to enhance the interaction between learners and medical staff, (3) effectiveness and efficiency due to the professional opinions from medial experts directly, (4) multimedia presentation to demonstrate multi-modality information, (5) learner-center design to promote active learning, and (6) on-line community to help cooperative learning. After being evaluated by the experts, focus group and adolescent users, it was found that the curriculum achieved its set goals. In addition, the design of the computer-human interface met the usability design guidelines, and helped motivate students' learning. By assisting adolescents to construct correct concept of diet, and to conduct healthy weight reduction behavior with the Internet Technology, it was concluded that the curriculum developed in this study could become an on-line curriculum model for future health education.