A pulley comprising a circumferential groove which has a non-flat groove surface for increased friction against a belt to be received and a manufacturing method therefor. According to the method a pulley material is forged into a basic pulley configuration which is the shape of the material ready for forming the circumferential groove. The basic configuration comprises a plurality of axial grooves which extend in a generally axial direction over a surface of the pulley in which the circumferential groove is to be formed. The the circumferential groove is rolling-formed in the pulley material. Thus, a non-flat groove surface for a higher friction is provided. Alternatively, the higher friction groove surface may be formed by roughening a sand blasting, shot blasting or chemical surface treatment.