This study attempts to use Skin of Allium sativum(Garlic) to the green synthesis of Skin of Allium sativum/zinc oxide nanoparticles as an adsorbent to remove Congo red, a toxic azo dye, from an aqueous solution. XRD, SEM, and FTIR tests were performed to determine the particles' characteristics. For the adsorption process, the ideal values for the process variables agitation time, adsorbent dosage, pH, initial dye solution concentration, and temperature were identified. The maximal adsorption capacity of synthesised Skin of Allium sativum/zinc oxide nanoparticles is 105.75 mg/g.