Objective To evaluate the effect of teaching method based on online resource-sharing mechanism in diagnostic teaching. Methods From September, 2019 to July, 2020, totally 720 students of 5-year curriculum of clinical medicine enrolled in 2017 in Hunan University of Medicine were selected and divided into experimental group and control group with 360 students in each. In the teaching of diagnostics, off-line teaching combined with online resource-sharing approach was adopted in the experimental group, while off-line traditional teaching approach was adopted in the control group. At the end of the teaching, theoretical examination method was used to compare the results of the two groups , and the questionnaire survey was used to investigate the experimental group students' evaluation on the effect of online resource-sharing method. Results Both midterm and final test scores of the experimental group [(83.25±5.72) and (85.14±7.65)] were significantly higher than those of the control group [(78.02±5.39) and (77.36±7.45)](all P<0.01). The results of the questionnaire survey showed that 85.0%(306/360) of the students in the experimental group believed that the network resource-sharing method in teaching of diagnostics greatly improved their autonomic learning capacity. Conclusions The teaching approaches of online resource sharing diagnostic course improves the learning outcomes and autonomic learning attitude of students.