The present invention aims to provide a method for improving discoloration in pulp, characterized by a versatile technique adaptable to any type of pulp, a time-saving process, a great and permanent anti-fading effect, environmental friendliness and other properties, as well as a pulp with greatly improved discoloration obtained by said method for improving discoloration. Discoloration in pulp can be greatly improved by adding one or more additives selected from the group consisting of reducing agents, peroxides and hydrogen-donating organic compounds to one of bleached mechanical pulp, semi-chemical pulps, chemical pulp and deinked pulps or a mixture of two or more of them, and irradiating it with UV and/or visible light.