The objective of this study is to explore the expression pattern, prognostic value, and functional role of RAB34 in gliomas. RAB34 messenger RNA (mRNA) expression was evaluated from low grade to high grade in 220 glioma patients of the Chinese Glioma Genome Atlas (CGGA). We therefore analyzed RAB34 mRNA expression in two validated datasets. For detecting the protein expression level of RAB34, another 104 glioma tissues were stained by immunohistochemistry. Gene ontology (GO) analysis and gene set variation analysis (GSVA) were used for functional annotation of RAB34. The mRNA and protein expression levels of RAB34 were both related to glioma grade progression and were inversely correlated with overall survival (OS) in high-grade glioma patients. GO analysis and GSVA showed that RAB34 sets related to migration were significantly enriched in the cases with RAB34 high expression. Pearson correlation analysis identified that genes including MMP-11, HSPB1, IGFBP2, HSPA6, IGFBP5, and MMP19 were positively correlated with RAB34. The expression of RAB34 is related to glioma grade progression and confers a poor prognosis in high-grade glioma patients.