A titanium product comprising an inner layer portion and a surface layer portion, wherein: a chemical composition of the surface layer portion consists, by mass%, of: O: 0.40% or less, Fe: 0.50% or less, Cl: 0.020% or less, N: 0.050% or less, C: 0.080% or less, H: 0.013% or less, O, N, C, Fe, H and impurities in a total content of 5% or less, the impurities including Sn, Mo, V, Mn, Nb, Mg, Si, Cu, Co, Pd, Ru, Ta, Y, La, Ce; and the balance: Ti; a chemical composition of the inner layer portion consists, by mass%, of: O: 0.40% or less, Fe: 0.50% or less, Cl: more than 0.020 and not more than 0.60%, N: 0.050% or less, C: 0.080% or less, H: 0.013% or less, O, N, C, Fe, H and impurities in a total content of 5% or less, the impurities including Sn, Mo, V, Mn, Nb, Mg, Si, Cu, Co, Pd, Ru, Ta, Y, La, Ce; and the balance: Ti; the inner layer portion has pores; in a cross-section perpendicular to a longitudinal direction of the titanium product, an area fraction of the pores of the inner layer portion is more than 0% and not more than 30%; and the titanium product satisfies formula (i) below: Cl I ≤ 0.03 + 0.02 × t S / t I where, the meaning of each symbol in formula (i) above is as follows: Cl I: Cl content (mass%) of inner layer portion t S: thickness of surface layer portion t I: thickness of inner layer portion, wherein the thickness of the surface layer portion and the thickness of the inner layer portion are measured according to the method disclosed in the description. O: 0.40% or less, Fe: 0.50% or less, Cl: 0.020% or less, N: 0.050% or less, C: 0.080% or less, H: 0.013% or less, O, N, C, Fe, H and impurities in a total content of 5% or less, the impurities including Sn, Mo, V, Mn, Nb, Mg, Si, Cu, Co, Pd, Ru, Ta, Y, La, Ce; and the balance: Ti; a chemical composition of the inner layer portion consists, by mass%, of: O: 0.40% or less, Fe: 0.50% or less, Cl: more than 0.020 and not more than 0.60%, N: 0.050% or less, C: 0.080% or less, H: 0.013% or less, O, N, C, Fe, H and impurities in a total content of 5% or less, the impurities including Sn, Mo, V, Mn, Nb, Mg, Si, Cu, Co, Pd, Ru, Ta, Y, La, Ce; and the balance: Ti; the inner layer portion has pores; in a cross-section perpendicular to a longitudinal direction of the titanium product, an area fraction of the pores of the inner layer portion is more than 0% and not more than 30%; and the titanium product satisfies formula (i) below: Cl I ≤ 0.03 + 0.02 × t S / t I where, the meaning of each symbol in formula (i) above is as follows: Cl I: Cl content (mass%) of inner layer portion t S: thickness of surface layer portion t I: thickness of inner layer portion, wherein the thickness of the surface layer portion and the thickness of the inner layer portion are measured according to the method disclosed in the description. O: 0.40% or less, Fe: 0.50% or less, Cl: more than 0.020 and not more than 0.60%, N: 0.050% or less, C: 0.080% or less, H: 0.013% or less, O, N, C, Fe, H and impurities in a total content of 5% or less, the impurities including Sn, Mo, V, Mn, Nb, Mg, Si, Cu, Co, Pd, Ru, Ta, Y, La, Ce; and the balance: Ti; the inner layer portion has pores; in a cross-section perpendicular to a longitudinal direction of the titanium product, an area fraction of the pores of the inner layer portion is more than 0% and not more than 30%; and the titanium product satisfies formula (i) below: Cl I ≤ 0.03 + 0.02 × t S / t I where, the meaning of each symbol in formula (i) above is as follows: Cl I: Cl content (mass%) of inner layer portion t S: thickness of surface layer portion t I: thickness of inner layer portion, wherein the thickness of the surface layer portion and the thickness of the inner layer portion are measured according to the method disclosed in the description. Cl I: Cl content (mass%) of inner layer portion t S: thickness of surface layer portion t I: thickness of inner layer portion, wherein the thickness of the surface layer portion and the thickness of the inner layer portion are measured according to the method disclosed in the description.