The adsorbent, activated carbon, was prepared from cattail by zinc chloride activation at 550 degrees C. A specific surface area analyzer and infrared spectrometer were used to characterize the activated carbon samples, and the influences of carbon dose, adsorption time, pH value, temperature, and initial adsorbate concentration were studied in batch adsorption experiments. The results showed that for the Ibuprofen solution with an initial concentration of 100 mg/L, the adsorption capacity was 241.94 mg/g under optimal conditions, i.e., dose of activated carbon 0.4 g/L, pH 3, temperature 30 degrees C, and reaction time 160 min. For the diclofenac solution with an initial concentration of 20 mg/L, the adsorption capacity was 47.14 mg/g under the optimal conditions, i.e., dose of activated carbon 0.4 g/L, pH 4, temperature 30 degrees C, and reaction time 120 min. The adsorption of IBP and DCF by cattail-derived activated carbon followed a pseudo-second-order kinetics model, and the Langmuir adsorption isotherm model best reflected the adsorption behavior. This paper not only provides a reference for the preparation conditions of activated carbon, realizes the resource utilization of Cattail plant residues, but also provides an economic and efficient approch for the treatment of wastewater containing IBP and DCF.