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To clarify which one has a different predominance of Th1 and Th2 immune responses in malignant and tuberculous pleural effusions. We did a meta-analysis of the results published previously to assess the levels of Th1/Th2 cytokines in two types of pleural effusion, and evaluated its ability to distinguish TPE from MPE. We queried the PubMed and Embase databases for studies indexed from 2000 up to March 2021. We included studies that (a) diagnosis of TPE and MPE by on culture, or pleural biopsy tissue provided; (b) compared levels of Th1/Th2 cytokines in pleural effusion between TPE and MPE. Pooled data by using a random-effects model or fixed-effects model, standardized mean differences (SMD) across studies comparing TPE and MPE. We also performed Egger test to assess of publication bias. Of 917 identified studies, a total of 42 studies were selected in the meta-analysis. Compared with malignant subjects, tuberculous subjects had a significant higher level of TNF-α [2.22, (1.60–2.84)], an elevated level of IFN-γ [3.30, (2.57–4.40)] in pleural effusion, a situation where the Th1 immune response dominates. Conversely, Interleukin-4 (IL-4) and IL-10 (Th2 cytokines) levels were higher in MPE than TPE. Besides, they were shown to be statistically insignificant tiny effects were [-0.15, (-0.94–0.63)], [-0.04, (-0.21–0.12)] respectively. We confirmed that pleural effusions caused by tuberculosis, a situation in which the Th1 cytokines are predominant. The slight preponderance of Th2 cytokines in malignant pleural effusions, which are not convincing enough to prove.