Tetracycline contamination adversely affects aquatic ecosystems and increases the likelihood of antibiotic-resistant bacterium development, posing substantial risks to both environmental and human health. Consequently, there is a pressing need for efficient technologies to break down and eliminate tetracycline from water sources. This study aimed to synthesis a Fe3O4/Chi-PVA@NiO composite for photocatalytic degradation of tetracycline. Crosslinked chitosan (Chi) and polyvinyl alcohol (PVA) were applied to enhance the mechanical strength and increasing the physical and chemical stability of composites. XRD, UV-DRS, SEM-EDS, VSM, and FTIR were employed for characterization. The composite material exhibits magnetic characteristic, evidenced by a saturation magnetization of 67.13 emu/g and a band gap measuring 1.86 eV. The magnetic characteristics enhance the separation efficiency of the composite following the photocatalytic process with an external magnet and low band gap values, which enable degradation to occur under visible light radiation. The maximum degradation efficiency was attained at a pH of 5, a tetracycline concentration of 20 mg/L, a composite dosage of 0.5 g/L, and an irradiation time of 100 min with a degradation efficiency of 98.20%. The rate of degradation kinetics approximates a pseudo-first-order model in which the value of the degradation constant decreases as the concentration of tetracycline increases. The catalyst exhibited outstanding stability and reusability, achieving a high degradation efficiency of 94.10% over five consecutive cycles. The FTIR analysis revealed no notable alterations in the functional groups of the composite both prior and following the photocatalytic degradation process. This research offers an efficient and eco-friendly approach for removing tetracycline contaminants from the environment.