Abstract: In order to assess the absorption of formaldehyde by chitosan fibers,nonwoven chitosan with aqueous formaldehyde solutions was treated under different conditions.The nonwoven chitosan fabric was first treated in sulfuric acid solutions with different pH in order to improve its reactivity to formaldehyde.Results showed that the chitosan fibers have obvious absorption properties for formaldehyde,with the maximum absorption capacity at 66.6 mg formaldehyde per gram fiber.pH of the pre-treatment solutions had some effect,whilst treatment temperature had little effect on the absorption properties.Because the fibers were in solid state during the treatment,the absorption rate was slow.In order for the fibers to fully absorb formaldehyde,the contact time should exceed 24 hours.