A workpiece holding jig for vibratory barreling configured to hold a single workpiece, when the workpiece is polished by a vibratory barreling device using polishing media, the workpiece being a disk-shaped member that has a circular through hole formed at a center portion thereof, having a diameter of 400 mm or more, and being formed in a flat shape having a large width with respect to a thickness, the workpiece holding jig comprising: disk-shaped first and second guard members (10, 11) each having an outer shape configured to, in use, be larger than the workpiece and disposed so as to face each other; and a holding member configured to, in use, hold the workpiece inside a columnar housing space so that the entire workpiece is located inside the housing space surrounded by the first guard member and the center of gravity of the workpiece matches completely or is near the center of gravity of the workpiece holding jig, the second guard member and an annular imaginary curved surface extending connecting the peripheral edges of the first and second guard members (10, 11); a covering member configured to, in use, contact and cover a non-polishing target area not polished by the polishing media in the workpiece; and a connection member extending between the peripheral edges of the first and second guard members (10, 11) and connecting the first and second guard members (10, 11) to each other, wherein each of the first and second guard members (10, 11) is provided with a first window portion (10w, 11w) communicating with the housing space, and wherein the connection member is provided with a second window portion communicating with the housing space, and wherein the imaginary curved surface, the first window portion (10w, 11w), and the second window portion are configured to allow the polishing media to pass between the inside and outside of the housing space. disk-shaped first and second guard members (10, 11) each having an outer shape configured to, in use, be larger than the workpiece and disposed so as to face each other; and a holding member configured to, in use, hold the workpiece inside a columnar housing space so that the entire workpiece is located inside the housing space surrounded by the first guard member and the center of gravity of the workpiece matches completely or is near the center of gravity of the workpiece holding jig, the second guard member and an annular imaginary curved surface extending connecting the peripheral edges of the first and second guard members (10, 11); a covering member configured to, in use, contact and cover a non-polishing target area not polished by the polishing media in the workpiece; and a connection member extending between the peripheral edges of the first and second guard members (10, 11) and connecting the first and second guard members (10, 11) to each other, wherein each of the first and second guard members (10, 11) is provided with a first window portion (10w, 11w) communicating with the housing space, and wherein the connection member is provided with a second window portion communicating with the housing space, and wherein the imaginary curved surface, the first window portion (10w, 11w), and the second window portion are configured to allow the polishing media to pass between the inside and outside of the housing space.