Aim To explore the impact of renin through angiotesin Ⅱ-independent mechanisms on calcification of rat vascular smooth muscle cells in vitro, and its molecular mechanisms.Methods Primary cultured cells were obtained by tissue-piece inoculation. Calcification of cultured rat vascular smooth muscle cells was produced by incubation with β-glycerophosphate and sodium pyruvate. The vascular smooth muscle cells were divided into 6 groups: the blank control group (cultured in normal medium), the calcification group (incubated in calcified medium), the calcification＋angiotesinⅡ receptor blocker group (cultured in calcified medium, giving Losartan 10^－6 mol/L to block AT1 and PD123,319 10^－5 mol/L to block AT2), calcification＋renin group (incubated in calcified medium, giving Losartan 10^－6 mol/L and 10^－5 mol/L PD123, 319, then added 10^－10, 10^－9, and 10^－8 mmol/L renin). Calcification was confirmed by Von Kossa staining. Calcium content and alkaline phosphatase (ALP) activity were measured to estimate the extent of calcification. The mRNA expression of core binding factorα1 (Cbfα1) and transforming growth factor-β1 (TGF-β1) was measured by competitive quantitative RT-PCR. The expression of Cbfα1 protein content was measured by Western blot. Results Compared with the blank control group, the calcium content and ALP activity of the calcification group in creased significantly, as well as the mRNA expression of Cbfα1, TGF-β1 and the expression of Cbfα1 protein increased significantly (P<0.01). Compared with calcification group, calcification＋ angiotensin Ⅱ receptor blocker group had no difference on calcification of vascular smooth muscle cells. Compared with calcification＋angiotensin Ⅱ receptor blocker group, intervention of rennin (10^－10, 10^－9, 10^－8 mmol/L) in a dose-dependent manner further promoted the calcium content and the ALP activity of rat vascular smooth muscle cells, as well as the mRNA expression of Cbfα1, TGF-β1 and Cbfα1 protein expression (P<0.05).Conclusions Renin can promote β-glycerophosphate-induced calcification of vascular smooth muscle cells through angiotesin Ⅱ-independent mechanisms, the mechanisms of renin promoted calcification of vascular smooth muscle cells through angiotesin Ⅱ-independent way may be through promoting the expression of TGF-β1, Cbfα1.