A caliper for an opposed piston type disc brake comprising: an inner body disposed on an inner side of a rotor in an axial direction and including at least one inner cylinder portion (10a, 10b) and a pair of attachment boss portions (11a, 11b) disposed on both outer sides of the at least one inner cylinder portion (10a, 10b) in a circumferential direction, the pair of attachment boss portions (11a, 11b) each having a bolt insertion hole (14a, 14b) penetrating therethrough in a radial direction; an outer body disposed on an outer side of the rotor in the axial direction and including at least one outer cylinder portion (21a, 21b); and a pair of side bridges (7, 8) disposed so as to cover the rotor from a radially outer side, and connecting, in the axial direction, end portions of the inner body on both outer sides in the circumferential direction and end portions of the outer body on both outer sides in the circumferential direction, wherein at least one of the pair of side bridges (7, 8) includes a concave portion extending in the axial direction and opening to an outer surface of the side bridge (7, 8), and a first beam portion and a second beam portion disposed so as to sandwich the concave portion from both sides, end portions of the respective first beam portion and the second beam portion on the inner side in the axial direction being connected to the attachment boss portions (11a, 11b) directly or via portions of the side bridges (7, 8) located near the attachment boss portions (11a, 11b), characterized in that the end portion of the first beam portion on the inner side in the axial direction is connected to the attachment boss portion (11a, 11b) via a boss connecting portion, and the boss connecting portion constitutes an inner side portion of the side bridge (7, 8) in the axial direction. an inner body disposed on an inner side of a rotor in an axial direction and including at least one inner cylinder portion (10a, 10b) and a pair of attachment boss portions (11a, 11b) disposed on both outer sides of the at least one inner cylinder portion (10a, 10b) in a circumferential direction, the pair of attachment boss portions (11a, 11b) each having a bolt insertion hole (14a, 14b) penetrating therethrough in a radial direction; an outer body disposed on an outer side of the rotor in the axial direction and including at least one outer cylinder portion (21a, 21b); and a pair of side bridges (7, 8) disposed so as to cover the rotor from a radially outer side, and connecting, in the axial direction, end portions of the inner body on both outer sides in the circumferential direction and end portions of the outer body on both outer sides in the circumferential direction, wherein at least one of the pair of side bridges (7, 8) includes a concave portion extending in the axial direction and opening to an outer surface of the side bridge (7, 8), and a first beam portion and a second beam portion disposed so as to sandwich the concave portion from both sides, end portions of the respective first beam portion and the second beam portion on the inner side in the axial direction being connected to the attachment boss portions (11a, 11b) directly or via portions of the side bridges (7, 8) located near the attachment boss portions (11a, 11b), characterized in that the end portion of the first beam portion on the inner side in the axial direction is connected to the attachment boss portion (11a, 11b) via a boss connecting portion, and the boss connecting portion constitutes an inner side portion of the side bridge (7, 8) in the axial direction.