Abstract: A rotary shaft for compressor includes a cylindrical shaft body and a cylindrical eccentric member. The shaft body is rotatably arranged in an outer box of the compressor and is connected to an electric motor at one end portion thereof. The eccentric member has a through hole extending along the axis thereof and formed eccentric thereto, and also has a groove extending from the upper end face to the lower end face thereof to form a passage for lubrication oil. The groove is provided with a bottom face adjacent to the shaft body. The shaft body is inserted into the through hole. The eccentric member is secured to the other end portion of the shaft body by laser-welding the bottom of the groove to the shaft body. An annular eccentric roller is rotatably fitted onto the eccentric member.