Objective SV40 T antigen had been used widely in establishment of transgenic tumor animal models, which could induce cellular immortalization and carcinogenesis. The objective of the study was to construct the eukaryotic specific expression vector of SV40 large T antigen in gastric parietal cells and to establish transgenic mouse models with microinjection technique. Methods 38kb DNA fragment HSUP>+/SUP>KSUP>+/SUP>ATPase β promoter/SV40T was released from specific expression vector of SV40 large T antigen in gastric parietal cells pcDNA31(-)/HKSV and injected into oocytes to establish transgenic mice. Transgenic positive mice were detected by PCR and Southern blotting. Gene expression was measured by RT-PCR. Results 422 injected eggs were transferred to 16 pseudopregnant female mice and 77 offspring were born, the frequency of transplant was 18.2%. In 77 liveborn mice, 2SUP># /SUP>, 4SUP>#/SUP> , 8SUP>#/SUP> , 16SUP>#/SUP> , 24SUP>#/SUP> , 51SUP>#/SUP> , 57SUP>#/SUP> , 61# , 68# , 73# were proved to be positive founder mice by PCR. 68# founder was sterile, and 99 F1 mice were borne by the other nine founders. None F1 positive mouse was found in 8# offspring, 31 F1 mice were proved to be positive by PCR and Southern blotting in the other eight pedigrees. The rate of positive mice was