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PURPOSE The high expression across multiple tumor types and restricted expression in normal tissues make B7-H3 an attractive target for immunotherapy. So far, little is known about the clinical significance of B7-H3 expression in meningiomas. Thus, we conducted the present study to address this issue in a cohort of 242 patients from a single institution. METHODS Expression profiles of immune checkpoint proteins (PD-L1, B7-H3, LAG3, PD-1 and VISTA) were explored by immunohistochemistry (IHC) in a meningioma test-cohort (n = 8). The roles of B7-H3 expression was further assessed in an expanded patient cohort (n = 234) using immunohistochemical tissue microarray analysis. RESULTS B7-H3 expression was significantly greater than all immune checkpoint proteins studied in tested cohort. B7-H3 was detected with different degrees in all meningioma specimens, predominantly on tumor cell membranes and in cytoplasm. The tumors were classified as B7-H3 high or low group pending on IHC histoscore (median histoscore = 111.06; range, 7.313-212.008). B7-H3 expression was statistically correlated with patient gender (p = .0297), tumor histopathological subtypes (p = .0262) and radiotherapy after surgery (p = .0028). However, no significant differences were observed in patient age, tumor location, grade and extent of resection between these two groups. Similarly, there was no significant difference in progression-free survival (PFS) and overall survival (OS) between patients of B7-H3 high or low group. CONCLUSIONS Our study indicates variable expression and clinical role of B7-H3 in meningiomas, suggesting its potential as an immunotherapeutic target in the future.