Using chitosan modified by cinnamaldehyde to decorate carbon nanotubes, a novel cinnamaldehyde/ chitosan/ carbon nanotubes composites were synthesized. The modified composites and its corresponding intermediates were characterized by FT-IR, XRD, high-resolution SEM and TGA. Taking porcine pancreatic lipase as a model, explored the properties of cinnamaldehyde/ chitosan/ carbon nanotubes composite materials. The results indicated that when the conditions were: molar ratio of cinnamaldehyde to chitosan of 41, pH =7.0 and the enzyme concentration of 5 mg/mL, and the maximum load of 248 mg/g and the enzyme activity of 8 064 U/g were obtained. The enzyme activity was still above 69% after seven recycles.