Abstract: The influence of four formaldehyde capture agents on the free formaldehyde content and viscosity of urea-formaldehyde resin have been explored. The results indicated that when the mass ratio between the protein of leather waste and sodium sulfite was 1∶2, and the free formaldehyde content of urea-formaldehyde resin was 0.160% and the viscosity was 17.2 s, respectively. The physical properties of particleboard prepared by this adhesive can meet with the national standard. The combination of the protein of leather waste and sodium sulfite can effectively inhibit the free formaldehyde in urea-formaldehyde resin and enhance its viscosity, which can expand the application area of the protein of leather waste.