Abstract: Imbalance of fatty acids in dietary intake is one of the main causes of inducing chronic metabolic syndrome,which threatened the health of mankind. The in vitro cellular model was employed and the evaluation indexes,including cell proliferation,cell membrane integrity,inflammatory factor,and intracellular lipid accumulation,were detected. Therefore,the dietary fatty acids,oleic acid,palmitic acid,as well as the two fatty acids' complex,were selected to assess how the excess dietary lipids influence on liver health in this work. This study demonstrated that the different dietary fatty acids exhibited different effects on liver cells.Palmitic acid shows higher cytotoxicity than oleic acid.Palmitic acid can induce cell apoptosis and disrupt the cell membrane integrity at lower doses.However,oleic acid,with the lower cytotoxicity,can cause the lipid accumulation in liver cells more easily.As far as the mixed fatty acids( oleic acid / palmitic acid,2∶ 1 ratio),although they exhibit lower cytotoxicity,inducing the lipid steatosis easily in liver cells was also observed.The experimental results for provides theory basis for reasonable dietary fat intake.