MicroRNAs (miRNAs) are endogenous non-coding RNAs, participating in diverse pathways that regulate tumor occurrence and progression. Hepatocellular carcinoma (HCC) is one of the most common malignancies, with poor prognosis due to lack of effective treatment modalities at present. Studies have showed that miR-122 plays an important suppressive role in genesis and progression of HCC, so it may probably become a novel biomarker for diagnosis and prognosis as well as therapeutic target of HCC. Here, the authors present the research progress in relationship between miR-122 and HCC.