Abstract Representation form and explanation mechanism of chemical micro cognition is a kind of model imaginative thinking in nature. This study found that there were some problems in chemistry teachers' teaching design on students constructing micro model imagination, such as no model constructing in teaching objectives, no delicate designing on imaginative thinking from macro facts to micro inference, lack of consciousness for leading students to understand substances and their changes on micro level, no corresponding explanation discourse on model imagination, lack of constructive activity design on model imagination. The main reasons were that the teachers were lack of epistemological analysis of micro content and lack of exquisite understanding on mechanism of students constructing micro cognition, and there also were problems in curriculum design. This paper expounded the basic strategies to solve these problems, such as teachers' forming a good habit of epistemological analysis of knowledge, taking system design on students' constructing model imagination, and optimizing curriculum design.
