Objective To practice and evaluate clinical reasoning oriented teaching method in the internship of pulmonary and critical care medicine. Methods From September 2019 to June 2021, 62 students enrolled in 2015 and in 2016 majoring by Clinical Medicine of the Air Force Military Medical University and experiencing clinical internship of pulmonary and critical care medicine were selected as subjects. Thirty three students from grade 2016 were trained by clinical reasoning oriented as experimental group and 29 students from grade 2015 trained by classic and traditional method as control. The training outcomes were evaluated by combination of records of stage evaluation and process evaluation. T-test was utilized to show the potential significant difference. Results The total scores of students from the experimental group were higher than those from the control group[(88.03 ± 3.74) vs. (83.28 ± 3.88)] among the internship in pulmonary and critical care of medicine. In the stage evaluation[(52.55 ± 2.73) vs. (49.90 ± 2.24)] and process evaluation[(35.48 ± 2.33) vs. (33.78 ± 2.86)], the scores of students in the experimental group were higher than those in the control group, the differences were statistically significant (all P<0.05). The composition of students' practice scores was analyzed. In the phased evaluation, there were significant differences between the experimental group and the control group in single choice questions [(17.55±1.37) vs. (16.48±1.45)] and brief answer questions 2 [(8.45±0.83) vs. (7.93±1.09)] (all P<0.05). As to the process evaluation, the scores from the test group in the evaluation indexes such as medical history collection [(8.46±1.14) vs. (7.86±1.22)], medical records writing [(13.61±0.89) vs. (12.97±1.57)] and case report [(8.82±1.18) vs. (8.14 ± 1.13)] were higher than those from the control group with statistical significance (all P<0.05). Conclusions Clinical reasoning oriented teaching method provide strong support to students' performance in the clinical training stage in pulmonary and critical care of medicine, which tailor clinical practice and so is able to cultivate a reasoning pathway for development of clinical post-competence from the perspective of medical routines.