An optical fiber sheet (10) comprises an optical fiber (11) and a wire rod (12) that are arranged between a first sheet and a second sheet. The optical fiber (11) is a multimode optical fiber having a core that is formed of quartz glass to which a refractive index modulation material is added. The optical fiber (11) has a numerical aperture of 0.30 or less and a flexural rigidity of 0.50 Nmm2 or less and is arranged between the first sheet and the second sheet in a bent state. The wire rod (12) intersects with the optical fiber (11) between the first sheet and the second sheet.
