A method for manufacturing a ring-shaped member, comprising: a forging step of forming a joined body from a round bar material, the joined body comprising a plurality of circular-shaped cylindrical portions (4A1, 4B1, 4A2, 4B2) coupled with each other; a cutting and separating step of cutting and separating the joined body to obtain a plurality of cylindrical members; and a rolling step of expanding an inner diameter size of a part of the plurality of cylindrical members to obtain a ring-shaped member, wherein the joined body comprising a first cylindrical portion (4A1), a third cylindrical portion (4A2), a second cylindrical portion (4B1), and a fourth cylindrical portion (4B2), by radially coupling each other, the third cylindrical portion (4A2) having an outer diameter size configured to be almost identical to an inner diameter size of the first cylindrical portion (4A1), the second cylindrical portion (4B1) having an outer diameter size configured to be almost identical to an inner diameter size of the third cylindrical portion (4A2), the fourth cylindrical portion (4B2) having an outer diameter size configured to be almost identical to an inner diameter size of the second cylindrical portion (4B1), characterized in that the rolling step comprises expanding an inner diameter size of a third cylindrical member (5A2) such that the third cylindrical member (5A2) has an inner diameter size almost identical to an inner diameter size of a first cylindrical member (5A1) to obtain a third ring-shaped member (6A2), and expanding an inner diameter size of a fourth cylindrical member (5B2) such that the fourth cylindrical member (5B2) has an inner diameter size almost identical to an inner diameter size of a second cylindrical member (5B1) to obtain a fourth ring-shaped member (6B2). a forging step of forming a joined body from a round bar material, the joined body comprising a plurality of circular-shaped cylindrical portions (4A1, 4B1, 4A2, 4B2) coupled with each other; a cutting and separating step of cutting and separating the joined body to obtain a plurality of cylindrical members; and a rolling step of expanding an inner diameter size of a part of the plurality of cylindrical members to obtain a ring-shaped member, wherein the joined body comprising a first cylindrical portion (4A1), a third cylindrical portion (4A2), a second cylindrical portion (4B1), and a fourth cylindrical portion (4B2), by radially coupling each other, the third cylindrical portion (4A2) having an outer diameter size configured to be almost identical to an inner diameter size of the first cylindrical portion (4A1), the second cylindrical portion (4B1) having an outer diameter size configured to be almost identical to an inner diameter size of the third cylindrical portion (4A2), the fourth cylindrical portion (4B2) having an outer diameter size configured to be almost identical to an inner diameter size of the second cylindrical portion (4B1), characterized in that the rolling step comprises expanding an inner diameter size of a third cylindrical member (5A2) such that the third cylindrical member (5A2) has an inner diameter size almost identical to an inner diameter size of a first cylindrical member (5A1) to obtain a third ring-shaped member (6A2), and expanding an inner diameter size of a fourth cylindrical member (5B2) such that the fourth cylindrical member (5B2) has an inner diameter size almost identical to an inner diameter size of a second cylindrical member (5B1) to obtain a fourth ring-shaped member (6B2).