A method for producing a grain oriented electrical steel sheet, the method comprising: a hot rolling process of hot-rolling a steel piece to obtain a hot rolled steel sheet, the steel piece including, as a chemical composition, by mass%, 0.030 to 0.100% of C, 0.80 to 7.00% of Si, 0.01 to 1.00% of Mn, 0 to 0.060% in total of S and Se, 0.010 to 0.065% of acid soluble Al, 0.004 to 0.012% of N, 0 to 0.30% of Cr, 0 to 0.40% of Cu, 0 to 0.50% of P, 0 to 0.30% of Sn, 0 to 0.30% of Sb, 0 to 1.00% of Ni, 0 to 0.008% of B, 0 to 0.15% of V, 0 to 0.20% of Nb, 0 to 0.10% of Mo, 0 to 0.015% of Ti, 0 to 0.010% of Bi, and a balance consisting of Fe and impurities; a cold rolling process of cold-rolling the hot rolled steel sheet to obtain a cold rolled steel sheet; a decarburization annealing process of decarburization-annealing the cold rolled steel sheet to obtain a decarburization annealed sheet; an annealing separator applying process of applying and drying an annealing separator including MgO to the decarburization annealed sheet; a final annealing process of final-annealing the decarburization annealed sheet after applying the annealing separator to obtain a final annealed sheet; an annealing separator removing process of removing a redundant annealing separator from a surface of the final annealed sheet; and an insulation coating forming process of forming an insulation coating on the surface of the final annealed sheet, wherein, in the decarburization annealing process, PH 2 O/PH 2 which is an oxidation degree of an atmosphere is 0.01 to 0.15, an annealing temperature is 750 to 900°C, and a holding is 10 to 600 seconds, wherein, in the annealing separator applying process, the annealing separator further includes MCl which is at least one selected from chlorides of an alkali metal, an alkaline earth metal, and Bi, and MCl / MgO which is a mass ratio of MgO and MCl is 2 to 40%, wherein, in the final annealing process, an oxidation degree is 0.00010 to 0.2 when an atmosphere includes a hydrogen, or a dew point is 0°C or less when an atmosphere consists of an inert gas without a hydrogen, and wherein, in the insulation coating forming process, an insulation coating forming solution in which a phosphoric acid and a metal compound are included and in which a mass ratio of the phosphoric acid and the metal compound is 2:1 to 1:2 is applied and is baked at 600 to 1150°C, and after decreasing a temperature to room temperature, an insulation coating forming solution in which a phosphate and a colloidal silica are included and in which a metal compound is not included is applied and is baked at 600 to 1150°C, in order to form the insulation coating. a hot rolling process of hot-rolling a steel piece to obtain a hot rolled steel sheet, the steel piece including, as a chemical composition, by mass%, 0.030 to 0.100% of C, 0.80 to 7.00% of Si, 0.01 to 1.00% of Mn, 0 to 0.060% in total of S and Se, 0.010 to 0.065% of acid soluble Al, 0.004 to 0.012% of N, 0 to 0.30% of Cr, 0 to 0.40% of Cu, 0 to 0.50% of P, 0 to 0.30% of Sn, 0 to 0.30% of Sb, 0 to 1.00% of Ni, 0 to 0.008% of B, 0 to 0.15% of V, 0 to 0.20% of Nb, 0 to 0.10% of Mo, 0 to 0.015% of Ti, 0 to 0.010% of Bi, and a balance consisting of Fe and impurities; a cold rolling process of cold-rolling the hot rolled steel sheet to obtain a cold rolled steel sheet; a decarburization annealing process of decarburization-annealing the cold rolled steel sheet to obtain a decarburization annealed sheet; an annealing separator applying process of applying and drying an annealing separator including MgO to the decarburization annealed sheet; a final annealing process of final-annealing the decarburization annealed sheet after applying the annealing separator to obtain a final annealed sheet; an annealing separator removing process of removing a redundant annealing separator from a surface of the final annealed sheet; and an insulation coating forming process of forming an insulation coating on the surface of the final annealed sheet, wherein, in the decarburization annealing process, PH 2 O/PH 2 which is an oxidation degree of an atmosphere is 0.01 to 0.15, an annealing temperature is 750 to 900°C, and a holding is 10 to 600 seconds, wherein, in the annealing separator applying process, the annealing separator further includes MCl which is at least one selected from chlorides of an alkali metal, an alkaline earth metal, and Bi, and MCl / MgO which is a mass ratio of MgO and MCl is 2 to 40%, wherein, in the final annealing process, an oxidation degree is 0.00010 to 0.2 when an atmosphere includes a hydrogen, or a dew point is 0°C or less when an atmosphere consists of an inert gas without a hydrogen, and wherein, in the insulation coating forming process, an insulation coating forming solution in which a phosphoric acid and a metal compound are included and in which a mass ratio of the phosphoric acid and the metal compound is 2:1 to 1:2 is applied and is baked at 600 to 1150°C, and after decreasing a temperature to room temperature, an insulation coating forming solution in which a phosphate and a colloidal silica are included and in which a metal compound is not included is applied and is baked at 600 to 1150°C, in order to form the insulation coating.