Abstract: Objective To observe expression difference of associated protein such as CD34, FAPα and α-SMA in activated fibroblasts among tissues of transplantation tumor in rat model， tissues adjacent to tumor and normal gastric tissues and to evaluate the role of fibroblast activated state in tumor growth. Methods Sixteen rats were randomly divided into model group（n=12） and normal control group（n=4）. Walker-256 cell lines were taken as the origin of rats model. Rat model was established by OB glue adhesive method. All rats raised at the same conditions. After 16 days， the tumor tissue， tissue adjacent to tumor and normal gastric tissue were removed. Expression of CD34， FAPα and α-SMA in these tissues was observed by immunohistochemical technique， Western blotting and RT-PCR. Results Compared with normal control group，expression of CD34 in tumor group and tissue adjacent to tumor group was significant lower（P＜0.05）. But expression of FAPα and α-SMA in these groups was higher than control group （P＜0.05）. There were different expression between tumor tissue and tissue adjacent to tumor in FAPα and α-SMA（P＜0.05）. Conclusion The different expression of CD34， FAPα and α-SMA in tumor tissue， tissue adjacent to tumor and normal gastric tissue indicated that there is correlation between fibroblasts activation and tumor development.