The adsorption and removal of chlortetracycline (CTC) from water on peanut shells decorated with magnetic particles under ultrasonic were studied. The morphology, components, functional groups, magnetic properties and BET surface area of peanut shells before and after decorated with magnetic particles were characterized. Further, the effects of contact time, temperature and initial pH value on adsorption were investigated. Meanwhile, the adsorption kinetics and regeneration performance were studied. The CTC adsorption of magnetic peanut shells can reach 82.96%, and the adsorption behavior of CTC by magnetic peanut shells can be described using pseudo-second-order kinetics model. Finally, the adsorption capacity of CTC merely decreases by 9.52% after recycling five times, and solid-liquid separation can be easily achieved under magnetic field applied.Graphical Abstract: