A hole-assisted optical fiber includes a core portion and a cladding portion that includes an inner cladding layer, an outer cladding layer, and holes formed around the core portion. A diameter of the core portion is 3 μm to 9.8 μm, a relative refractive index difference of the core portion relative to the outer cladding layer is 0.11% to 0.45%, an outside diameter of the inner cladding layer is 53 μm or less, a relative refractive index difference of the inner cladding layer relative to the outer cladding layer is a negative value, −0.30% or more, a diameter of each hole is 2.4 μm to 4.0 μm, a hole occupancy rate is 17% to 48%, a bending loss at a wavelength of 1625 nm when bent at a radius of 5 mm is 1 dB/turn or less, and a cut-off wavelength is 1550 nm or less.