To achieve the aims of green chemistry, persimmon tannin-propane-melamine-Zirconium (PT-Pr-Me-Zr) was synthesized as a bio-based bifunctional heterogeneous catalyst polymer. Persimmon tannin was used as a biopolymer for the synthesis of bio-organic catalyst, and the properties of PT-Pr-Me-Zr were characterized using X-ray powder diffraction, Fourier transform infrared spectroscopy, thermogravimetric analysis, Energy-dispersive X-ray spectroscopy, and field emission scanning electron microscopy. The as-synthesized composite was applied for the Knoevenagel condensation between aromatic aldehyde derivatives and malononitrile, then the conditions of reaction such as solvent and catalyst loading amount were optimized. The bifunctional property of PT-Pr-Me-Zr catalyst was improved the yield and rate of Knoevenagel reaction. The PT-Pr-Me-Zr can be recovered for five times, which was illustrated the reusability of catalyst. Based on the findings, the PT-Pr-Me-Zr can be applied as an inexpensive and ecofriendly catalyst in organic reaction such as Knoevenagel condensation.