目的：阐明结核－聚合酶链反应（ＴＢ－ＰＣＲ）在诊断结核性胸腔积液中的作用。方法：以胸膜活检病理结果为标准，总结了１１８例胸腔积液ＴＢ－ＰＣＲ的检测结果，并与结核菌涂片、培养两种方法进行了对比。结果：ＴＢ－ＰＣＲ、涂片、培养三种方法的阳性率分别为３３％，０和５％，前者高于后两者（Ｐ＜０．００１）。但ＴＢ－ＰＣＲ的假阴性率较高（６７％）。结论：用ＴＢ－ＰＣＲ法诊断结核性胸腔积液的价值有限，最好做胸膜活检确诊 Objective: To clarify the role of tuberculosis-polymerase chain reaction (TB-PCR) in the diagnosis of tuberculous pleural effusion. Methods: According to the results of pleural biopsy, the results of 118 cases of pleural effusion TB-PCR were summarized and compared with those of tuberculosis smear and culture. Results: The positive rates of TB-PCR, smear and culture were 33%, 0% and 5% respectively, the former was higher than the latter two (P <0.001). However, the false-negative rate of TB-PCR was high (67%). Conclusion: The value of TB-PCR in the diagnosis of tuberculous pleural effusion is limited, it is best to do a pleural biopsy