This article presents the development, description, application, and discussion of an analytical framework to examine students' drawings of scientific concepts and processes. Student-generated representation, particularly drawing, is increasingly emphasised as an important learning strategy to help students reason, explain, and demonstrate their scientific thinking and understanding. Although this strategy would require a greater need to understand what students are drawing, there are currently few frameworks that can support researchers and educators in analysing student-generated drawings. Based on the theory of social semiotics and an empirical data corpus of students' drawings from two research projects, we developed an analytical framework to describe and categorise a broad range of ideas and relationships that students are representing through their drawings in physics and chemistry. The application of this framework will be illustrated by two analytical examples of students' drawings in the topics of rotational moment and chemical bonding. The first example analysed students' drawings in relation to their accompanying written explanations, while the second example analysed the students' drawings in conjunction with the occurring classroom discourse. Through the illustration, the research and pedagogical applications and usefulness of this analytical framework will be discussed.