〔Abstract〕 Objective To study the expression of CYFIP1 gene in HCC tissue and its biological mechanism in the development of hepatocarcinoma(HCC). Methods The expression of CYFIP1 in 80 pairs HCC tissues was evaluated by staining of tissue microarray slides(TMA), and its clinical relevance was evaluated. The apoptosis assay was conducted with Annexin V-FITC/PI staining. The expression of CYFIP1 in HepG2 cells was performed with Western blot. Results The expression of CYFIP1 in HCC tissues was lower than that in adjacent normal liver tissues(P=0.031), which was clinically relevant with tumor grades, tumor size and prognosis of HCC patients. Knock down of CYFIP1 by shRNA in HepG2 cells increased the proliferation(P=0.019) and decreased the apoptosis(P=0.021) of HepG2 cells. Conclusion CYFIP1 is a suppressor gene in HCC, which may be a potential prognostic marker in HCC.