Objective:To investigate the effects of miRNA-26a (miR-26a) on the target gene HMGA2 on the proliferation and migration of hepatoma cells and the underlying mechanism. Methods:Liver cancer tissue samples ( n = 30) and adjacent normal tissue samples ( n = 30) pathologically confirmed by Wenzhou Hospital of Traditional Chinese Medicine between September 2018 and September 2019 were collected. MiR-26a mimics, control mimics (miR-Control), high-mobility group A2 protein (HMGA2) siRNA or negative control siRNA (Control) were transfected into human hepatoma cell lines HepG2 or Huh-7 cells. The expression of miR-26a in hepatocellular carcinoma tissue was detected by reverse transcription quantitative polymerase chain reaction (RT-qPCR). MTT assay and scratch test were performed to determine the ability of cell proliferation and migration. RT-qPCR and western blotting were performed to detect miR-26a and HMGA2 mRNA expression. The relationship between miR-26a and HMGA2 mRNA was analyzed using Bioinformatics and luciferase reporter gene assay. Results:RT-qPCR results showed that the expression level of miR-26a in hepatocellular carcinoma tissue was 0.11 ± 0.02, which was significantly lower than that in normal tissues (0.25 ± 0.03, t = 21.268, P < 0.05). The expression level of miR-26a in stage III + IV was 0.05 ± 0.01, which was significantly lower than that in stage I + II (0.09 ± 0.01, t = 15.491, P < 0.05). Cell experiment showed that in the miR-26a group, the proliferation ability of Huh-7 cells was (3.10 ± 0.30) and (4.10 ± 0.40), and the proliferation ability of HepG2 cells was (3.08 ± 0.31) and (4.11 ± 0.40), which was significantly lower than that in the control group [(3.90 ± 0.40), (5.50 ± 0.60), (3.92 ± 0.41), (5.49 ± 0.58), t = 8.764, 10.634, 11.148, 10.728, all P < 0.05]. In the miR-26a group, the migration ability was (0.50 ± 0.06), (0.65 ± 0.07), which was significantly lower than that in the control group [(1.00 ± 0.10), (0.96 ± 0.10), t = 23.483, 13.910, both P < 0.05]. Bioinformatics and in vitro experiments showed that HMGA2 was a direct target of miR-26a. Restoring the expression of HMGA2 in miR-26a mimics-transfected cells, compared with that in the miR-26a group [(0.24 ± 0.02), (0.31 ± 0.03);(0.45 ± 0.05)], could significantly reverse the inhibitory effect of miR-26a on tumor cell proliferation and migration [(0.31 ± 0.03), (0.40 ± 0.04);(0.93 ± 0.08), t = 10.634, 9.859, 27.868, all P < 0.05). Conclusion:miR-26a inhibits the proliferation and migration of hepatoma cells by directly targeting HMGA2. The abnormal decrease of miR-26a and the increase of HMGA2 may be the important factors that participate in the occurrence and development of liver cancer.