In this study, a zinc (II) complex was synthesized with a Schiff base ligand derived from orthovanillin and ortho-phenylenediamine. The formation of the obtained complex and the coordination of the ligand to the metal center were confirmed by various spectroscopic techniques, including infrared (IR), ultraviolet-visible (UV-Vis), thermogravimetric analysis (TGA), and nuclear magnetic resonance (NMR).The optical band gap of the complex, determined via UV-Vis spectroscopy and Tauc analysis, reveals a direct transition at 3.75 eV, confirming its semiconducting nature. The photocatalytic activity of the complex was evaluated under UV irradiation for the degradation of two widely used organic dyes: methylene blue (MB) and crystal violet (CV). Several parameters were studied to optimize the degradation efficiency, including the mass of the photocatalyst, the volume of hydrogen peroxide (H₂O₂), and the effect of sunlight. Results revealed that the complex exhibits excellent photocatalytic efficiency, particularly under UV light in the presence of hydrogen peroxide, with degradation rates exceeding 95% for both dyes under optimal conditions (catalysts mass = 4.5 mg, H₂O₂ volume = 4.4 mL for MB and 5.4 mL for CV). Moreover, the study highlights the potential of this Zn-based catalyst for environmental applications, offering an effective and sustainable approach for treating dye-contaminated wastewater.