This study aimed to investigate the antiproliferative effect of aqueous and organic extracts of mulberry leaves (Morus Alba L.) on human hepatocellular carcinoma HepG2 cell line. Mulberry leaf extracts were prepared using the solvents: water, 50% aqueous MeOH, and 100% MeOH for different time intervals, while the cells treated with dimethyl sulfoxide (DMSO) served as control. The effects of aqueous and organic extracts of M. alba L. leaves on HepG2 cell viability, nuclear factor kappa B (NF-κB) gene expression, alfa-fetoprotein (AFP), albumin (ALB), gamma-glutamyl transpeptidase (γ-GT) and alkaline phosphatase (ALP) were measured. The results of the cell viability assays showed that water, 50% aqueous MeOH, and 100% MeOH extracts exhibited a highly significant inhibitory effect on HepG2 cell proliferation which was evidenced by a reduction in viable cell count. The results were confirmed by microscopical examination of cell morphology. Furthermore, the mulberry leaf extracts suppressed the activity of NF-κB gene expression of HepG2 cells compared to the control. Also a highly significant depression occurred at the levels of AFP, γ-GT and ALP in HepG2 cells compared with that of controls in a time dependent manner. By contrast, the mulberry leaf extracts increased the secretion of ALB. Therefore, the conclusion was that the organic and aqueous extracts of mulberry leaves inhibit the growth of HepG2 cells through suppressing the activity of NF-κB gene expression and modulate the biochemical markers.