Objective To reveal the role of Phosphatidylinositol 3-kinases (PI3Ks) in regulating human diploid fibroblast (2BS cell) senescence as well as the possible mechanisms involved. Methods Using a P13Ks specific inhibitor, LY294002, cell cycle, apoptosis, proliferation, senescence association p-galactosidase staining as well as senescence association CKIs, p16(INK4) and p21(Cip1) protein expressions were all measured in the low passages of 2BS cells. Results Both 25 mumol/L and 50 mumol/L concentrations of LY294002 could cause a significant decrease in cells entering into S phase, and this cell cycle of G(1) phase arrest was dose-dependent. Meanwhile, LY294002 contributed to apoptosis, caused 2BS cell growth arrest, and activated senescence association beta-galactosidase (P <0.05). In addition, LY294002 could induce time-course expressions of p16(INK4) and p21(Cip1) in 2BS cell lines. Conclusions P13Ks inhibitor LY294002 could induce senescence-like changes in 2BS cell lines. Two senescence associated CKIs, p16INK4 and p21(Cip1), might be involved in this senescence phenotype proceeding in 2BS cell lines.