Objective: To investigate the carcinogenesis of malignant transformation cells by comparing the difference in transfection efficiency of exogenous plasmids through liposome between normal cells and malignant transfected cells. Methods: Two types of plasmids that express the fluorescent proteins were transfected with liposome into cells such as 16HBE and its malignant transformation cells induced by crystalline nickel sulfide and antibenzo (a) pyrene separately, and the transfection were observed by fluorescent microscope. Results:In a range of cell density, the transfection efficiency of normal cells 16HBE is lower than that of the malignant transfected cells both with the plasmids eGFP and GFPLC3. Conclusion:Inconsistency in membrane permeability between normal cells and malignant transfected cells leads to inconsistency in transfection efficiency.