In this study, a new adsorbent derived from sunflower husk powder and coated in CuO nanoparticles (CSFH) was investigated to evaluate the simultaneous adsorption of Levofloxacin (LEV), Meropenem (MER), and Tetracycline (TEC) from an aqueous solution. Significant improvements in the adsorption capacity of the sunflower husk were identified after the powder particles had been coated in CuO nanoparticles. Kinetic data were correlated using a pseudo-second-order model, and was successful for the three antibiotics. Moreover, high compatibility was identified between the LEV, MER, and TEC, isotherm data, and the Langmuir model, which produced a better fit to suit the isotherm curves. In addition, the spontaneous and exothermic nature of the adsorption process was crucial for transforming the three antibiotics into CSFH. The greatest CSFH adsorption capacity was in MER (131.83 mg/g), followed by TEC (96.95mg/g), and LEV (62.24 mg/g). These findings thus indicate that CSFH is one of the most effective and efficient adsorbents to use for eliminating wastewater contaminated with antibiotic residue.