Animal experiments are a major part of medical education. At present, there are some problems in the laboratory animal ethics teaching mode, such as low popularization and limited teaching method. To resolve these problems, we focused on education of laboratory animal ethics and 3R theory ( reduction, replacement, and refinement) to help medical students enhance their laboratory animal ethics knowledge. The flipped classroom design of animal ethics is a student-leading classroom. Before class, a teacher transfers knowledge to students on an online platform. In class, the teacher guides the student groups to discuss and analyze the animal experiment protocol to enhance the research ability of students.