We demonstrated for the first time that E6 but not E7 inhibits the antitumor activity of LKB1 in lung cancer cells by downregulating the expression of KIF7 and the antitumor activity of LKB1 was determined by two factors, one was phosphorylation of LKB1, the other was that p‐LKB1 must be located in the cytoplasm, both were indispensable. The gene discussed is KIF7; the disease is lung carcinoma.