MicroRNAs (miRs) have emerged as key epigenetic regulators involved in cancer progression. miR-320a has been demonstrated to be a novel tumor suppressive microRNA in several types of cancers. In the present study, the role of miR-320a in human hepatocellular carcinoma (HCC) was investigated. The expression levels of miR-320a and messenger RNA were determined by reverse transcription-quantitative polymerase chain reaction, while cell cycle and cell apoptosis were analyzed by flow cytometry. The cell proliferative ability was determined by Cell Counting Kit-8 assay and colony formation assay. The downstream target of miR-320a was confirmed by luciferase reporter assay, while the protein levels were measured by western blotting. The results revealed that miR-320a was inversely associated with HCC proliferation in HCC cell lines. Functional studies demonstrated that miR-320a significantly decreased the capability of cell proliferation and induced G0/G1 growth arrest in vitro. In addition, β-catenin was identified as one of the direct targets of miR-320a, downregulating the expression level of β-catenin, c-myc, cyclin D1 and dickkopf-1. In conclusion, miR-320a may act as a tumor-suppressive microRNA through targeting β-catenin in HCC.