Abstract: Objective To analyze the condition of misdiagnosis (over-diagnosis) in the new-registered pulmonary tuberculosis in Shanghai and to find the ways for reducing misdiagnosis.Methods All the new-registered tuberculosis (TB) cases that were withdrawn because of being misdiagnosed from 1998 to 1999 in Shanghai were included in the analysis.The indicators like kinds of diseases misdiagnosed,the distribution of hospital provided misdiagnosis,the duration of delay for diagnosis and the time for anti-tuberculosis treatment,and the impact on tuberculosis control.Results The total misdiagnosing rate was 4.2%.The first three diseases be misdiagnosis were lung cancer,pneumonia and pulmonary parasite.The misdiagnosis rates in general hospitals,municipal tuberculosis hospital and district (county) tuberculosis hospital was 4.5%,4.0%,4.2%,respectively.The doctor-delay was 74.1 days for misdiagnosis as TB and then is diagnosis as other diseases.Conclusion Accurate diagnosis is an important premise for finding and curing pulmonary tuberculosis patients,especially for the smear negative patients.It is necessary to develop gold standard to diagnose smear negative tuberculosis.It is essential that to establish and perfect the regular meeting on tuberculosis prevention and chemotherapy.For the difficult and complicated cases,doctors of several departments should provide final diagnosis.

Key words: Tuberculosis,pulmonary, Misdiagnosis