An optical fiber includes a core portion and a cladding portion that is formed on an outer periphery of the core portion and has a refractive index lower than a maximum refractive index of the core portion. Characteristics at a wavelength of 1550 nm are an effective core area of a fundamental propagation mode of equal to or larger than 120 μm2, an effective core area of a first higher-order propagation mode of equal to or larger than 170 μm2, and an effective refractive index of the first higher-order propagation mode of larger than the refractive index of the cladding portion by equal to or larger than 0.0005.