The present invention provides a method for reducing the content of a metal catalyst in a biodegradable and absorbable polymer that can be applied on an industrial scale and a method for producing a biodegradable and bioabsorbable polymer having a metal catalyst content of less than 1 ppm in terms of a metal. The method includes the steps of (1) copolymerizing lactide and ε-caprolactone at a molar ratio ranging from 40/60 to 60/40 or 65/35 to 85/15 in the presence of the metal catalyst to produce a copolymer; and (2) washing the copolymer with a mixed solvent comprising acetic acid and isopropanol at a volume ratio ranging from 25/75 to 45/55 or 45/55 to 55/45 at less than 40° C., and drying the copolymer.