The present invention provides a method for preserving recycled fiber by using biocides and a method for manufacturing paper using recycled fiber. The method for manufacturing paper, using recycled fiber as a raw material, comprises pulping procedure: pulping the raw material containing recycled fiber, and papermaking procedure: producing the paper with the pulp slurry obtained in the pulping procedure; wherein the total starch content of recycled fiber is measured before recycled fiber is pulped, and when the total starch content of recycled fiber is higher than a predetermined value, one or more biocides are added during the pulping procedure.