The invention discloses a two-dimensional zinc coordination polymer and a preparation method thereof. The complex belongs to monoclinic system, a P21/n space group, with a two-dimensional layered structure, wherein two Zn2+ ions, a completely deprotonated ligand and two coordination water are in the structural unit. 1,3-dipropyl (3,5-dicarboxylic phenol) is used as a ligand, zinc nitrate is used as a metal source in the invention, and the target polymer is synthesized by hydrothermal method with the advantages of simple preparation process, low cost, good repeatability and the like, providinga certain basis for synthesis and research of transition metal complexes. The solid fluorescence emission spectra of ligand and complexe are tested at the room temperature. The results indicate that both the ligand and the complex have the fluorescence property, and when the excitation wavelength is 335nm, the maximum emission wavelength of the ligand and the complex is 424 and 455nm, respectively.