BACKGROUND AND AIMS: Researches have shown that miRNAs have been proposed as novel diagnostic biomarkers for classification and prognostic stratification of HCC. However, whether or not miR-431 contributes to the progression of HCC remains unknown. Therefore, we aimed to investigate the clinicopathological significance of miR-431 in HCC. METHODS: MiR-431 expression in 95 HCC cases and corresponding adjacent non-cancerous tissues was evaluated by quantitative reverse transcription polymerase chain reaction (qRT-PCR). Furthermore, statistical analysis was performed to identify the correlations between expression of miR-431 and a variety of clinicopathological parameters and patient recurrence. The area under the receiver operating characteristic curve (AUC) was used to evaluate the accuracy of miR-431 as a biomarker for HCC diagnosis and prediction of disease deterioration. RESULTS: MiR-431 was markedly down-regulated in the HCC samples (1.1885 ± 0.75867) compared with corresponding adjacent tumor tissues (1.7957 ± 0.89333, P < 0.001). The AUC of low miR-431 expression to diagnose HCC was 0.668 (95 % CI 0.592-0.744, P < 0.001). MiR-431 down-expression was correlated with multiple malignant characteristics, including lymph node metastasis (r = -0.455, P < 0.001), clinical TNM stage (r = -0.223, P = 0.030), MTDH (r = -0.292, P = 0.006), vaso-invasion (r = -0.204, P = 0.047), MVD (r = -0.281, P = 0.006) and HCV (r = 0.215, P = 0.037). Additionally, the recurrent time of lower miR-431 expression group was 56.602 ± 3.914 months, much longer than that in the high expression group (50.009 ± 2.731 months), however, no significant difference was noted (χ (2) = 0.005, P = 0.943). CONCLUSIONS: The down-expression of miR-431 is partially responsible for a series of clinicopathological features which may be tightly correlated with the progression of HCC. Thus, expression of miR-431 may be proposed as a new factor in association with the progression of HCC.