Abstract: Objective To explore the application of case teaching method (CBL) combined with problem oriented teaching method (PBL) in clinical teaching of thoracic surgery. Methods A total of 68 clinical medical undergraduate interns who interned in the department of thoracic surgery of the First affiliated hospital of Bengbu medical college from April 2016 to February 2018 were selected as the research objects, and were randomly divided into a double-blind control group and an observation group, with 34 interns in each groups. There was no statistically significant difference in age, gender, education background and other general data between the two groups (P>0.05), which were comparable. Approval was accessed from the ethics committee of Bengbu medical college and informed consent was gained. In the control group, the traditional teaching method was used for clinical teaching, which was conducted by general ward rounds, guiding the removal of drainage tube for surgical dressing change and knowledge lectures. The observation group adopted the dual-track teaching method of CBL and PBL. The two groups were compared for their examination results and the recognition and satisfaction of the teaching methods of the interns. Results There was no significant difference between the theoretical knowledge score of the control group (90.36±3.38) and the observation group (91.84±3.54), P>0.05, while the skill operation score (89.31±3.18) and case analysis score (90.57±3.24) of the observation group were significantly higher than those in the control group (83.14 ±2.27, 84.21±2.38), all P<0.05. The recognition degree of the observation group was higher than that of the control group (all P<0.05). Conclusion The application of CBL combined with PBL in the clinical teaching of thoracic surgery is helpful to improve the performance of skill operation and case analysis of intern students, and the teaching results are well received.