This systematic review and meta-analysis aimed to establish the prognostic impact of tumor-infiltrating lymphocytes (TILs) on survival outcomes in cancer. The study included studies that examined the prognostic significance of CD3+, CD4+, CD8+, and FoxP3+ lymphocytes in solid tumors. The results showed that CD3+ and CD8+ TILs had a positive effect on survival, with hazard ratios (HRs) of 0.58 (95% CI 0.43–0.78) and 0.71 (95% CI 0.62–0.82), respectively. FoxP3+ regulatory TILs did not show a significant impact on overall survival (HR 1.19, 95% CI 0.84–1.67). The CD8/FoxP3 ratio produced a more significant HR (0.48, 95% CI 0.34–0.68) but was used in fewer studies. The study concluded that future research should be carefully designed to prevent overestimating the effect of TILs on prognosis, and ratios between TIL subsets may provide more informative results.This systematic review and meta-analysis aimed to establish the prognostic impact of tumor-infiltrating lymphocytes (TILs) on survival outcomes in cancer. The study included studies that examined the prognostic significance of CD3+, CD4+, CD8+, and FoxP3+ lymphocytes in solid tumors. The results showed that CD3+ and CD8+ TILs had a positive effect on survival, with hazard ratios (HRs) of 0.58 (95% CI 0.43–0.78) and 0.71 (95% CI 0.62–0.82), respectively. FoxP3+ regulatory TILs did not show a significant impact on overall survival (HR 1.19, 95% CI 0.84–1.67). The CD8/FoxP3 ratio produced a more significant HR (0.48, 95% CI 0.34–0.68) but was used in fewer studies. The study concluded that future research should be carefully designed to prevent overestimating the effect of TILs on prognosis, and ratios between TIL subsets may provide more informative results.