Abstract: Objective To investigate the expression and significance of peroxisome proliferator-activated receptor γ(PPAR-γ)in gastric cancer patients and gastric cell line SGC7901.Methods SP immunohistochemistry was used to investigate PPAR-γ expression in 50 cases of gastric cancer,their adjacent tissues and the SGC7901.Results The positive rate of PPAR-γ protein expression was significantly higher in gastric cancer(58%)than that in their adjacent mucosa(28%)(P＜0.01).The expression of PPAR-γ was positive in SGC7901,and it was significantly high in poor differentiation,infiltration of serosa,lymph node metastasis(P＜0.01)and advanced tumor stage(P＜0.05).It was irrelevant with gender,age,tumour size and location(P＞0.05).Conclusion Expression of PPARγ protein is up-regulated in gastric cancer.PPAR-γ is not only relevant with gastric cancer happening and its progression.There may be a molecular marker and prognostic factor of gastric cancer.