The telomerase activity assay has been established for the detection of malignant pleural effusion (MPE), however, the overall diagnostic accuracy of the telomerase activity assay for MPE remains unclear. We performed a systematic search in the Pubmed, Embase and Cochrane databases to identify published studies that have evaluated the diagnostic role of the telomerase activity assay for M PE. Sensitivity, specificity and other measures of accuracy of the telomerase activity assay in the diagnosis of MPE were pooled using the random effects models. A summary receiver operating characteristic (SROC) curve was used to summarize overall test performance. A total of eight studies met the inclusion criteria for the meta-analysis. The pooled sensitivity and specificity for diagnosing MPE were 0.76 [95% confidence intervals (Cl), 0.72-0.80] and 0.87 (95% Cl, 0.83-0.91), respectively. The positive likelihood ratio was 5.19 (95% CI, 2.36-11.42), the negative likelihood ratio was 0.25 (95% Cl, 0.11-0.53) and the diagnostic odds ratio was 23.18 (95% Cl, 6.11-87.83). The area under the SROC curve was 0.92. The telomerase activity assay plays a role in the diagnosis of MPE with a relatively high specificity. The results of a telomerase activity assay should be interpreted together with the combination of other test results and clinical findings.