In this current research work, hydrogel composite polymer of sodium alginate-g-(polyacrylicacid-co-Sodium4-vinylbenzenesulfonate)/zinic oxide hydrogel (SA-g-(PAAc-co-VBS)/ZnO has been synthesized to be an efficient adsorbent for cationic dye namely crystal violet (CV). The physicochemical properties of the synthesized compound were identified via several characterization techniques such as Fourier transform infrared (FTIR), Field emission scanning electron microscope (FE-SEM), Thermo gravimetric analysis (TGA), X-ray diffraction (XRD), and Transmission electron microscopes (TEM). The adsorption kinetics and equilibrium isotherm of (SA-g-(PAAC-co-VBS)/ZnO towards CV removal were best fitted the pseudo-first-order and Freundlich isotherm models respectively (Qe =956.56 mg/g ) at optimum condition temperatures 30 oC, Conc.= 200 mg. L-1, pH= 6.6, and weight of surface 0.04 g/100 ml. Recyclability and Desorption studies indicated the best recycling performance at 3 cycles of using (SA-g-(PAAC-co-VBS)/ZnO), with a significant efficiency >80%. Depend on the results, the synthesized SA-g-(PAAc-co-VBS)/ZnO can be applied as a promising, eco-friendly, cost-effective, and efficient adsorbent for cationic dye removal.