Objective:To investigate the relationship of PPP4R1 gene with the oncogenesis and metastasis of gastric carcinoma by using bioinformatics analysis, and to verify the result by RT-PCR.Methods: IntNetDB was used to search for the neighborhoods of gene PPP4R1 and cliques by CFinder；Chilibot was used to explore the association between the cliques and carcinoma, then the association of PPP4R1 with gastric carcinoma was deduced. Eighteen pairs of primary and metastatic specimens from the same patient and 12 pairs primary carcinoma and the adjacent normal specimens from the same patient were analyzed by RT-PCR for PPP4R1 expression. Results: It was found that the community genes of PPP4R1 included PPP2R5E, MTMR4, PPP3CC, CTDP1, CTDSP1, FLJ22405, PPP1CB, PPP1CC, PPP2R2A, PPP2R5A, PPP2R5C, CTDSP2, and PPP1CA as searched by Cfinder2.0 when k=14. Nine of the genes were associated with carcinoma and 2 associated with carcinoma and metastasis. The result of RT-PCR showed that higher expression of PPP4R1 was found in 15 of the 18 primary gastric cancer specimens compared with the paired metastatic specimens (P<0.01); higher expression was also found in 9 of the 12 adjacent normal specimens compared with the paired cancer specimens (P<0.01). Conclusion: Gene PPP4R1 may be associated with the oncogenesis and metastasis of gastric carcinoma；bioinformatics is an efficient way to investigate function of new genes.