A new complex [Zn(3,4-APT)₂(H₂O)₄]·8H₂O (1, 3,4-HAPT = 4-(5-(pyridin-3-yl)-4H-1,2,4-triazol- 3-yl) benzoic acid) has been prepared and characterized by elemental analysis, X-ray single-crystal diffraction analysis, thermogravimetric analysis and infrared spectrum analysis. Theoretical calculation based on density functional theory (DFT) is also employed to explicate frontier orbitals of 3,4-HAPT. X-ray single-crystal diffraction analysis reveals that 1 belongs to the triclinic system, space group P with a = 7.5123(3), b = 8.6745(3), c = 15.2074(6) Å, α = 78.469(1), β = 87.387(1), γ = 65.448(1)°, V = 882.42(6) Å, Z = 1, D_c = 1.528 g·cm^–3, μ = 0.780 mm^–1, M_r = 812.09, F(000) = 424, the final R = 0.0401 and wR = 0.1136. Zn(II) ion is coordinated by two N atoms from two 3,4-HAPT as well as four O atoms from four coordinated water molecules, forming a 0D motif with distorted octahedral coordinated geometry. The adjacent 0D units are linked into a 3D supramolecular structure through hydrogen bonding interaction. In addition, complex 1 exhibits better antifungal activity against Colletotrichum gloeosporioides Penz than the ligand and metal salt by MIC, MBC tests and Kirby-Bauer disc diffusion method which exhibit potential application in the antifungal fields.