Retinoblastoma susceptibility gene(Rb gene)is a tumor suppressor,which often deleted,mutated or inactivated in many malignant tumors.We construct an antisense Rb gene expression vector DOLRBAS and transfected it into human embryonic lung fibroblast(HEL cells)by electroporation technique.With the transient expression of antisense Rb gene the Rb protein synthesis is reduced and the growth rate of HEL cells in increased,but no coloney of HEL cells formed in soft agar.This result indicates that Rb gene can block cell division of HEL cells,but inactivation of Rb gene only is not sufficient for malignancy transformation of HEl cells. （Chin J Ocul Fundus Dis,1993,9:198-201）