Provided are a polymer article excellent in mechanical strength, toughness, and stretchability and a production method of the polymer article. The polymer article of the present invention is formed of a polymer material and is a polymer blank or a formed polymer body. The polymer article of the present invention has a crystallinity of not less than 50% but less than 90% and a tensile strain at fracture of not less than 60%. A method for producing a polymer article of the present invention includes: a heating step of heating the polymer material to a temperature of not lower than (Tm−70)° C. but lower than Tm(° C.) where Tm is the melting point (° C.) of the polymer material; and a compression step of cooling the polymer material heated in the heating step and compressing the polymer material in the course of the cooling to obtain a polymer article having a crystallinity of not less than 50% but less than 90% and a tensile strain at fracture of not less than 60%.