This article argues the design of the recyclable Z-scheme g-C3N4/Fe3O4/Bi2WO6/Bi2S3 (CNFBB) photocatalyst as an efficient concept to obtain photogenerated charge carriers with high redox potential. A cost-effective magnetic CNFBB nanocomposite was fabricated via a multistep method by decorating Fe3O4, Bi2WO6, and Bi2S3 on the surface of pure g-C3N4 nanosheets. The photocatalytic capability was demonstrated for the visible-light degradation of tetracycline antibiotic (TC) in an aqueous solution. Sophisticated analytical techniques such as XRD, FTIR, elemental mapping, EDS, SEM, AFM, TEM, VSM, DRS, PL, and BET were employed for the characterization of synthesized nanomaterials. The CNFBB catalyst showed improved TC degradation activity (98 % in 105 min) under LED illumination with a remarkable degradation rate of 0.0341 min−1, which is 2.27 times higher than that of ternary CNFB. The improved photocatalytic ability was ascribed to the synergistic impacts of g-C3N4, Fe3O4, Bi2WO6, and Bi2S3 by developing a quaternary CNFBB nanostructure with a high surface area, lower band gap energy, high stability, easily recycled, excellent redox potential, and an efficient charge separation mechanism. Interestingly, the CNFBB hybrid displayed good reusability and high stability after six cycles of experiments. The photodegradation mechanism was charge migration pathways, and band locations were systematically explained by the Z-scheme heterojunction system verified by radical quenching experiments, ESR results, and band structure calculation. This work can open new horizons in designing other Bi-based systems supported by g-C3N4 nanosheets for wastewater purification.