In this study, biochar was produced from coffee husks and further functionalized with β-cyclodextrin to remove sodium dodecylbenzenesulfonate (SDBS) and cetylpyridinium chloride (CPC) surfactants from aqueous solution. The effect of pre-pyrolysis treatment of the coffee husks with NaOH, as well as the type of crosslinking agent, on the functionalization was evaluated. The biochars were characterized by FTIR, Raman spectroscopy, TGA, SEM, EDS, and chemical analysis. Adsorption kinetics and equilibrium isotherms were investigated in aqueous solutions. SDBS adsorption was not favored under all the investigated materials and conditions. The functionalized biochars showed better CPC removal (57.5 mg g−1 for glutaraldehyde functionalized biochar, and 113.6 mg g−1 for epichlorohydrin functionalized biochar) compared with non-functionalized biochars (55.8 mg g−1 for non-treated biochar and 35.1 mg g−1 for NaOH pre-treated biochar). The functionalized materials showed better CPC adsorptive capacity than prior literature reports. The adsorption data of CPC fit best to the Elovich kinetic model and Sips isotherm. Thermodynamic studies revealed that CPC adsorption is an endothermic process. The results indicated that β-cyclodextrin functionalization increased CPC removal, but electrostatic interactions acted as important mechanism for the adsorption. This work extends the range of applications for β-cyclodextrin-functionalized biochars by offering new design strategies for developing biochar-based adsorbents aimed at surfactant wastewater removal.