MicroRNA (miRNA) is a small non-coding RNA that contains 21 to 23 nucleotides and can down-regulate gene expression by translational repression.Recent studies found that some miRNAs might function both as oncogenes and tumor suppressors;its role in the tumorigenesis may complement and enrich the mechanisms of tumorigenesis.Liver cancer is a great threat to human health,whose pathogenesis is still not completely understood.MiRNAs can influence the tumorigenesis,differentiation and treatment of liver cancer.Here we summarizes the related progression in research of miRNA and liver cancer.