OBJECTIVE To analyze the discrepancies between clinical and autopsy diagnoses in hospitals of different grades and with respect to duration of hospitalization. METHODS A total of 188 autopsy cases collected from hospitals of different grades were retrospectively reviewed and the discrepancies between clinical and autopsy diagnoses were analyzed. RESULTS The overall rate of misdiagnosis was 48.9% (92/188). The misdiagnosis rate in grade I hospitals (75.8%, 25/33) was significantly higher than that in grade III (39.6%, 38/96; chi(2) = 12.861, P = 0.000) and grade II hospitals (49.2%, 29/59; chi(2) = 6.179, P = 0.016 ). The misdiagnosis rate of patients beyond 24 hours of admission was lower than that admitted within 24 hours (chi(2) = 20.991, P = 0.000). The overall rate of missed diagnosis was 34.6% (65/188). The rate of missed diagnosis in grade I hospitals was remarkably higher than that of the grade III hospitals (chi(2) = 8.241, P = 0.006). There was no difference between grades I and III hospitals on the rate of missed diagnosis within 24 hours of admission, however, this rate was lower in grade III hospitals in comparing with that of grade I hospitals in patients admitted beyond 24 hours (chi(2) = 5.181, P = 0.047). The distribution of disease entities commonly encountered in patients of both misdiagnosis and missed diagnosis were heart problems, infections, arterial diseases and pulmonary embolism. CONCLUSIONS The rate of discrepancies between clinical and autopsy diagnoses is relatively high. The misdiagnosis and missed diagnosis rate in grade I hospitals was significantly higher than that in grade III hospitals and was closely related with the duration of hospitalization. Autopsy study thus still remains an important measure in clinical audit.