A photonic crystal fiber having a plurality of holes arranged in quartz of the optical fiber in three concentric hole layers of hexagonal shapes along a longitudinal direction, wherein in a cross section, a hole ratio which is an area of the holes per unit area is larger in a central side than in an outer side in a portion corresponding to a cladding, characterized in that a distance A at hexagonal apices of a first hole layer and the second hole layer, the first hole layer comprising 18 holes at a same adjacent distance Λ1 between adjacent holes in the central side, the second hole layer comprising 18 holes at a same adjacent distance Λ2 between the adjacent holes outside the first hole layer and a third hole layer having 12 holes being all positioned adjacently at a distance Λ3 and outside of the second hole layer satisfies Λ 1 / Λ = 0.67 , Λ 2 / Λ = 1.0 , Λ 3 / Λ = 2.0 , a diameter d of all the holes are the same, and, when the distance Λ is represented in a horizontal axis and d/Λ is represented in a vertical axis, the distance Λ and the diameter d of all the holes are in a region where respective regions represented by mathematical formulas C4 overlap, an effective cross-sectional area is 500 μm 2 or more, a loss in an LP31 mode is 0.1 dB/m or more so that the LP31 mode is not propagated, at light of a wavelength range of 1.05 μm or more to 1.07 μm or less, and a bending loss of a basic mode is 1 dB/km with a bending radius of 500 mm or less in the wavelength range. [Mathematical Formulas C4] d / Λ ≤ 0.22 Λ − 2.01 Λ ≦ 11 μ m d / Λ ≤ 0.407 11 μ m ≦ Λ ≦ 18.7 μ m d / Λ ≤ 0.00333 Λ + 0.345 Λ ≥ 18.7 μ m d / Λ ≥ 0.00167 Λ + 0.323 Λ ≦ 14.5 μ m d / Λ ≥ 0.00625 Λ + 0.255 Λ ≥ 14.5 μ m in a cross section, a hole ratio which is an area of the holes per unit area is larger in a central side than in an outer side in a portion corresponding to a cladding, characterized in that a distance A at hexagonal apices of a first hole layer and the second hole layer, the first hole layer comprising 18 holes at a same adjacent distance Λ1 between adjacent holes in the central side, the second hole layer comprising 18 holes at a same adjacent distance Λ2 between the adjacent holes outside the first hole layer and a third hole layer having 12 holes being all positioned adjacently at a distance Λ3 and outside of the second hole layer satisfies Λ 1 / Λ = 0.67 , Λ 2 / Λ = 1.0 , Λ 3 / Λ = 2.0 , a diameter d of all the holes are the same, and, when the distance Λ is represented in a horizontal axis and d/Λ is represented in a vertical axis, the distance Λ and the diameter d of all the holes are in a region where respective regions represented by mathematical formulas C4 overlap, an effective cross-sectional area is 500 μm 2 or more, a loss in an LP31 mode is 0.1 dB/m or more so that the LP31 mode is not propagated, at light of a wavelength range of 1.05 μm or more to 1.07 μm or less, and a bending loss of a basic mode is 1 dB/km with a bending radius of 500 mm or less in the wavelength range. [Mathematical Formulas C4] d / Λ ≤ 0.22 Λ − 2.01 Λ ≦ 11 μ m d / Λ ≤ 0.407 11 μ m ≦ Λ ≦ 18.7 μ m d / Λ ≤ 0.00333 Λ + 0.345 Λ ≥ 18.7 μ m d / Λ ≥ 0.00167 Λ + 0.323 Λ ≦ 14.5 μ m d / Λ ≥ 0.00625 Λ + 0.255 Λ ≥ 14.5 μ m <EOS>