Previously, we found that G protein-coupled receptor APJ endogenous ligand apelin-13 stimulates vascular smooth muscle cells (VSMC) proliferation mediated in part by PKC-PI3K-ERK1/2-cyclinD1 signaling cascades. In this study, Raf-1-14-3-3 signaling in rat VSMCs proliferation stimulated by apelin-13 was further investigated. Cell proliferation was measured with MTT assay. Expression of PI3K, phospho-PI3K, Raf-1, phospho-Raf-1, ERK1/2, phospho-ERK1/2, cyclinD1 and cyclinE were detected by Western blotting. 14-3-3 protein combining with Raf-1 was detected by immunoprecipitation. Here, we demonstrated that apelin-13 increased the expression of 14-3-3, Raf-1 phosphorylation and ERK1/2 phosphorylation in a concentration- dependent and time-dependent manner at 0～4 μmol/L and 0～48 h. 14-3-3 inhibitor Difopein decreased the apelin-13-induced Raf-1 phosphorylation, ERK1/2 phosphorylation, expression of cyclinD1 and cyclinE. Furthermore, apelin-13 promoted the combination of 14-3-3 protein and Raf-1, Difopein significantly inhibited the combination of 14-3-3 and Raf-1 stimulated by apelin-13. Similarly, Difopein significantly inhibited the VSMCs proliferation stimulated by apelin-13. Our results revealed that Raf-1+14-3-3-ERK1/2 signaling cascades mediated the effect of apelin-13 on rat VSMCs proliferation .