Preparation of crosslinked chitosan/activated carbon composite adsorbent by water bath, composite adsorbent was characterized by scanning electron microscopy and fourier transform infrared spectroscopy, and tested for humic acid (HA) removal. The experimental results showed that compared with original activated carbon (AC), the HA adsorption capacity of compound adsorbent increased by 5mg/g. Acidic condition was beneficial to HA removal and cations all exhibited promotion on the uptake of HA. The HA adsorption capacity of compound adsorbent increased with the increase of adsorption time. The adsorption kinetics of HA removal by composite adsorbent agreed well with the pseudo-second-order model (R2 ≥ 0.99), and the adsorption isotherms were well fitted by the Langmuir model. The thermodynamic analysis suggested that HA removal by composite adsorbent was a spontaneous and endothermic process. The compound adsorbent can be recycled because of its good desorption and regeneration. It is positive meaning to give full play to value of AC and chitosan, and improve the quality and safety of drinking water.