This study focused on characterization and assessing the adsorption capabilities of sulfonated polyether ether ketone (SPEEK) and ionic liquid incorporated SPEEK (SPEEK-BIM) composite adsorbents for removing ciprofloxacin (CIP) from water. Fourier-transform infrared (FTIR) analysis verified successful sulfonation and interaction between the polymer and ionic liquid. Scanning electron microscopy (SEM) revealed structural changes, indicating increased surface roughness and the formation of pores after sulfonation. Thermogravimetric analysis (TGA) showed thermal stability and multiple degradation steps. Adsorption experiments demonstrated SPEEK and SPEEK-BIM's effectiveness, with maximum removal efficiencies of 75.8 % and 92.9 % respectively, at a solid/liquid ratio of 0.6 g/L. Equilibrium was reached within 300 min for SPEEK and 180 min for SPEEK-BIM, with pH 7–9 yielding optimal adsorption due to CIP's zwitterionic form. Calculated maximum adsorption capacities were found as 303.03 mg g−1 and 500.0 mg g−1 for SPEEK and SPEEK-BIM, respectively. Langmuir isotherm modeling indicated monolayer coverage, while pseudo second-order kinetics described chemisorption with active sites involvement. Thermodynamic analysis suggested spontaneous, endothermic adsorption favored at higher temperatures. Desorption studies demonstrated reusability, especially in basic conditions. Water medium affected adsorption, with reduced efficiency in drinking and tap water compared to distilled water. Comparisons with literature data highlighted competitive adsorption capacities. In conclusion, SPEEK and SPEEK-BIM composite adsorbents hold promise for CIP removal, with potential applications in water treatment and environmental remediation.