The paper selects over 20 online courses and analyses the subjects, organization, the way to show the content of the courses, the use of media, and design of the teaching in the case study of Chinese popular MOOC platform. On this basis, the paper summarizes the principles of curriculum design and design models in MOOC environment, such as practical course content, minimized but continuous course structure, simplified course content, the effective combination of the media with the content, learners-centered, and stressing social construction. The author is not only a member of the curriculum development team of MOOC, but also experiences the online courses as a learner, and tries to summarize the principles of curriculum design and design models after analyzing the design elements with the case study method. [For full proceedings, see ED557189.]