Catalase from bovine liver was lyophilized from an aqueous solution containing chitin-graft-poly(2-methyl-2-oxazoline) (3), which was synthesized by the reaction of 52% deacetylated chitin (1) with living poly(2-methyl-2-oxazoline) (2). The rate of consumption of H2O2 in chloroform catalyzed by the lyophilized catalase with 3 was enhanced more than 10 times that by catalase without 3. The dispersibility and solubility of lyophilized catalase with 3 in chloroform were improved in comparison with catalase itself.