Objective To examine the correlation of the expression of microtubule-associated protein light chain 3B (LC3B) with the numbers of CD68⁺ microglia, CD4⁺ T lymphocytes, and CD8⁺ T lymphocytes in different grades of gliomas and to investigate its significance.Methods LC3B expression in 127 gliomas tissues of different grades and 40 tumor-adjacent normal brain tissues was determined using immunohistochemistry (IHC) and Western blot. The numbers of CD68⁺ microglia, CD4⁺ T lymphocytes, and CD8⁺ T lymphocytes in these tissues were measured using IHC. The correlation between LC3B and the immune cells, as well as its significance, was analyzed.Results (1) IHC and Western blot showed that LC3B expression was significantly higher in low-grade gliomas than in tumor-adjacent normal brain tissues, and significantly higher in high-grade gliomas than in low-grade gliomas (all P<0.05). (2) The numbers of CD68⁺ microglia, CD4⁺ T lymphocytes, and CD8⁺ T lymphocytes were significantly higher in gliomas than in tumor-adjacent normal brain tissue (P<0.05), and significantly higher in high-grade gliomas than in low-grade gliomas (P<0.05). (3) LC3B expression was positively correlated with the numbers of CD68⁺ microglia, CD4⁺ T lymphocytes, and CD8⁺ T lymphocytes in low-grade and high-grade gliomas (low-grade gliomas:r=0.466, 0.599, and 0.537, all P<0.05; high-grade gliomas:r=0.657, 0.608, and 0.561, all P<0.05). (4) LC3B expression and the numbers of CD68+ microglia, CD4⁺ T lymphocytes, and CD8⁺ T lymphocytes in gliomas were significantly correlated with tumor size (P<0.05).Conclusions LC3B expression is positively correlated with the numbers of CD68⁺ microglia, CD4⁺ T lymphocytes, and CD8⁺ T lymphocytes in glioma tissues, and LC3B may be one of the factors that affect the cellular immunity of glioma patients.