An antireflection coating film formed on an optical base member includes: a first layer having a refractive index of N1 and a film thickness of D1; a second layer having a refractive index of N2 and a film thickness of D2; and a third layer formed of a fine concavo-convex structure, having a refractive index changing from N3 to 1.0, and a film thickness of D3, wherein the first, second, and third layer are formed in order from the optical base member side having a refractive index of Nsub, and wherein when the refractive indexes Nsub, N1, N2, and N3 are those taken when a wavelength is 550 nm, conditions for Nsub, N1, D1, N2, D2, N3 and D3 are satisfied.