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Flavan-3-ols are monomers of Proanthocyanidins (PAs), which are important polyphenolic compounds in grapes. Previous studies had shown that <i>VvMYBPA2</i> was closely related to grape flavan-3-ol monomers biosynthesis, but its regulatory network is still unclear. Here, we found that the contents of (+)-catechin and (−)-epicatechin, the enzyme activities of anthocyanidin reductase (ANR) and leucoanthocyanidin reductase (LAR) and the expression of <i>VvANR</i> and <i>VvLAR1</i> were increased in the <i>VvMYBPA2</i> overexpression grape leaves compared to the control. It was proved that VvMYBPA2 protein interacted with VvWDR1 and VvWDR1 protein interacted with VvMYC2 by yeast two-hybrid (Y2H) and bimolecular fluorescence complementation (BiFC). The promoters of <i>VvANR</i> and <i>VvLAR1</i> were bound by VvMYBPA2 using yeast one-hybrid (Y1H) assay. These results suggested that VvMYBPA2 could form a trimeric complex with VvWDR1 and VvMYC2 and jointly regulated the expression of flavan-3-ol monomers related genes <i>VvANR</i> and <i>VvLAR1</i>, thereby affecting the enzyme activities of ANR and LAR and ultimately regulating the contents of flavan-3-ols.