Objective To investigate the effects of down-regulation of B7-H3 on the biological characteristics of human hepatocellular carcinoma(HCC)cells, and to explore the clinical significance of down-regulation of B7-H3 on the development of HCC. Methods The proliferation, apoptosis, migration and invasion of HCC cells were observed by cell scratch and Transwell chamber techniques. The expression of B7-H3 in 80 HCC tissues and adjacent liver tissues was detected by immunohistochemical method, and the relationship between B7-H3 expression and clinicopathological parameters of HCC was analyzed. Results B7-H3 down-regulated HCC cell model was constructed by choosing SK-hep-1 and MHCC97L with high expression of B7-H3 and transfection of B7-H3 siRNA. The positive rate of B7-H3 in HCC tissues was 73.33%, which was significantly different from that in adjacent liver tissues(54.67%)(P=0.041). The positive rate of B7-H3 was positively correlated with the differentiation degree of HCC(P=0.012), recurrence time(P=0.001), and metastasis(P=0.007), but positively correlated with age, sex, and tumor size. Conclusions B7-H3 can be used as a potential indicator of recurrence and metastasis of HCC. Downregulation of B7-H3 expression may provide a new way to inhibit the invasion of HCC.