Tumor escape from the host immune system has been a major problem in immunotherapy of human malignancies.FasL/Fas-induced apoptosis plays an important role in various immunological processes.The aim of this study is to investigate the immune evasion in human lung carcinoma cell A549 induced by human lymphoma cell Jurkat via Fas/FasL pathway. The gene discussed is FAS; the disease is lung carcinoma.