Objective To evaluate the effect of case method combined with research-based learning model on the teaching of toxicology experimental teaching for undergraduates. Methods All 447 students from the grade 2012-2015 of preventive medicine in the School of Public Health of Guizhou Medical University were recruited.The traditional teaching method(n=110) and the research-based teaching method(n=337) were adopted respectively, and the test scores and questionnaires were used to evaluate the effect. Results The pass rate and excellent rate of inquiry teaching were 94.4%(318/337) and 33.5%(113/337), which were higher than those of traditional teaching methods[79.1%(87/110) and 8.2%(9/110)],and the difference is statistically significant(χ²=22.72,26.86,P<0.05). The results of the questionnaire showed that most of the students preferred the inquiry teaching(63.2%,60/95),and that the inquiry teaching improved self-learning(88.4%,84/95), problem-solving(82.1%,78/95),communication(91.6%,87/95) and team work(84.2%,80/95). Conclusions The case-directed inquiry teaching method improves the teaching effect of toxicology experiments and contributes to the improvement of students' comprehensive quality.