The expression of transforming growth factor α(TGFα)in human gastrointestinal carcinoma by methods of molecular hybridization and cell FIT cell-cycle analysis was investigated.The results show that the levels of TGFα mRNA are higher in gastric carcinoma tissues,colonic carcinoma tissues and rectal carcinoma tissues than in the corresponding control tissues. After treating with 12-O-tetradecanoylphorbol-13-acetate(TPA,100μg/L,4h),the level of TGFαmRNA in gastric carcinoma cell line(MGc80-3)increases，and percentage of S phase cells is markedly increased after 6 hours. These results suggest that TGF α plays an important role in gastrointestinal carcinoma tissues and expression of TGF α mRNA can be regulated by TPA.