An optical fiber ribbon (1A, 1B, 1C, 1D, 1E, 1F, 1G), comprising: a plurality of optical fibers (11A, 11B, 11C, 11D, 11E, 11F, 11G, 11H, 11J, 11K, 11L) disposed in parallel to each other; a connecting resin for connecting the plurality of optical fibers (11A, 11B, 11C, 11D, 11E, 11F, 11G, 11H, 11J, 11K, 11L); and a bridge portion (21a, 121a, 221a, 321a, 421a) formed of the connecting resin, wherein the plurality of optical fibers (11A, 11B, 11C, 11D, 11E, 11F, 11G, 11H, 11J, 11K, 11L) are disposed in a state where a side surface of the optical fiber (11A, 11B, 11C, 11D, 11E, 11F, 11G, 11H, 11J, 11K, 11L) is separated from or in contact with a side surface of another adjacent optical fiber (11A, 11B, 11C, 11D, 11E, 11F, 11G, 11H, 11J, 11K, 11L), wherein the bridge portion (21a, 121a, 221a, 321a, 421a) is provided between the optical fibers (11A, 11B, 11C, 11D, 11E, 11F, 11G, 11H, 11J, 11K, 11L) disposed in the separated state, wherein an outer diameter of the optical fiber (11A, 11B, 11C, 11D, 11E, 11F, 11G, 11H, 1 1J, 11K, 11L) is 220 μm or less, wherein an average distance between centers of the plurality of optical fibers (11A, 11B, 11C, 11D, 11E, 11F, 11G, 11H, 1 1J, 11K, 11L) is 220 μm or more and 280 μm or less, and a maximum thickness D of the optical fiber ribbon (1A, 1B, 1C, 1D, 1E, 1F, 1G) including the optical fiber (11A, 11B, 11C, 11D, 11E, 11F, 11G, 11H, 11J, 11K, 11L) is 235 μm or less, characterized in that the connecting resin has a Young's modulus of 0.5 MPa or more and 200 MPa or less at room temperature, and when a width of the bridge portion (21a, 121a, 221a, 321a, 421a) is defined as W, a thickness of the bridge portion (21a, 121a, 221a, 321a, 421a) is defined as t, and a Young's modulus at room temperature of the connecting resin is defined as E, a deformation parameter P represented by P = D × E × t 2 / W is 0.035 MPa.mm 2 or more and 14.2 MPa.mm 2 or less. a plurality of optical fibers (11A, 11B, 11C, 11D, 11E, 11F, 11G, 11H, 11J, 11K, 11L) disposed in parallel to each other; a connecting resin for connecting the plurality of optical fibers (11A, 11B, 11C, 11D, 11E, 11F, 11G, 11H, 11J, 11K, 11L); and a bridge portion (21a, 121a, 221a, 321a, 421a) formed of the connecting resin, wherein the plurality of optical fibers (11A, 11B, 11C, 11D, 11E, 11F, 11G, 11H, 11J, 11K, 11L) are disposed in a state where a side surface of the optical fiber (11A, 11B, 11C, 11D, 11E, 11F, 11G, 11H, 11J, 11K, 11L) is separated from or in contact with a side surface of another adjacent optical fiber (11A, 11B, 11C, 11D, 11E, 11F, 11G, 11H, 11J, 11K, 11L), wherein the bridge portion (21a, 121a, 221a, 321a, 421a) is provided between the optical fibers (11A, 11B, 11C, 11D, 11E, 11F, 11G, 11H, 11J, 11K, 11L) disposed in the separated state, wherein an outer diameter of the optical fiber (11A, 11B, 11C, 11D, 11E, 11F, 11G, 11H, 1 1J, 11K, 11L) is 220 μm or less, wherein an average distance between centers of the plurality of optical fibers (11A, 11B, 11C, 11D, 11E, 11F, 11G, 11H, 1 1J, 11K, 11L) is 220 μm or more and 280 μm or less, and a maximum thickness D of the optical fiber ribbon (1A, 1B, 1C, 1D, 1E, 1F, 1G) including the optical fiber (11A, 11B, 11C, 11D, 11E, 11F, 11G, 11H, 11J, 11K, 11L) is 235 μm or less, characterized in that the connecting resin has a Young's modulus of 0.5 MPa or more and 200 MPa or less at room temperature, and when a width of the bridge portion (21a, 121a, 221a, 321a, 421a) is defined as W, a thickness of the bridge portion (21a, 121a, 221a, 321a, 421a) is defined as t, and a Young's modulus at room temperature of the connecting resin is defined as E, a deformation parameter P represented by P = D × E × t 2 / W is 0.035 MPa.mm 2 or more and 14.2 MPa.mm 2 or less.