BACKGROUND Human brain glioma is the most common endocranial tumor; its mortality and morbidity are very high. The objective of this study was to determine whether miR-338-3p can regulate malignant biological behaviors of glioma cells by targeted silencing of MACC1. MATERIAL AND METHODS The expression of miR-338-3p was detected by quantitative real-time PCR in brain glioma tissues and cell lines. Bioinformatics software was used to predict some potential target genes of miR-338-3p. Luciferase activities assay was used to verify the combination between target genes and miR-338-3p. And MACC1 protein expression was detected by Western blot. The apoptosis and proliferation ability were analyzed by MTT and flow cytometry assay. RESULTS Compared with normal brain tissues and cells, miR-338-3p in glioma tissues and cell lines was confirmed to be expressed at low levels, and down-regulation of miR-338-3p tended to be correlated with worse histological grade. Up-regulation of miR-338-3p promoted apoptosis and sharply inhibited cell proliferation ability of U251 and U87 cells. The luciferase activities assay, biotin-avidin pull-down assay, and western blot analysis verified that MACC1 was a specific target gene of miR-338-3p. Subsequent experiments found that up-regulation of MACC1 significantly inhibited the apoptosis and increased the cell proliferation ability of U251 and U87 cells. The regulation effects of miR-338-3p on malignant biological behaviors of glioma cells can be partly reversed by up-regulation of MACC1. CONCLUSIONS Down-regulation of miR-338-3p was an independent prognostic biomarker associated with poor prognosis in glioma patients; miR-338-3p acted as a tumor-suppressing gene whose silencing can inhibit malignant biological behaviors of glioma cells. MACC1 was a specific target gene of miR-338-3p, which regulates malignant biological behaviors of glioma cells partly through directly silencing MACC1 expression.