A method of manufacturing a grain-oriented electrical steel sheet, the method comprising: reheating a steel slab in a temperature range of 1300 °C or less, the steel slab having a composition that contains, in mass% or mass ppm, C: 0.002% to 0.08%, Si: 2.0% to 8.0%, Mn: 0.005% to 1.0%, N: less than 50 ppm, S: less than 50 ppm, Se: less than 50 ppm, sol.Al: less than 100 ppm, at least one selected from: Sn: 0.010% to 0.200%; Sb: 0.010% to 0.200%; Mo: 0.010% to 0.150%; and P: 0.010% to 0.150%, and optionally at least one selected from: Ni: 0.010% to 1.50%; Cr: 0.01% to 0.50%; Cu: 0.01% to 0.50%; Bi: 0.005% to 0.50%; Te: 0.005% to 0.050%; and Nb: 10 ppm to 100 ppm, with a balance being Fe and incidental impurities; hot rolling the reheated steel slab into a hot rolled steel sheet; optionally hot band annealing the hot rolled steel sheet in a temperature range of 800 °C or more and not more than 1200 °C; cold rolling the hot rolled steel sheet once or twice or more with intermediate annealing in between, to form a cold rolled steel sheet having a final sheet thickness; performing decarburization annealing that also serves as primary recrystallization annealing, on the cold rolled steel sheet, wherein the decarburization annealing is divided into first and second stages, wherein annealing is performed in the first stage in a temperature range of 800 °C or more and 900 °C or less that eases decarburization, and annealing is performed in the second stage at a temperature which is higher than the temperature at which the annealing is performed in the first stage; applying an annealing separator to a surface of the steel sheet after the decarburization annealing; and performing final annealing on the steel sheet with the annealing separator applied to develop the secondary recrystallized texture and also to form a forsterite film, wherein a relationship Td ≥ Tf is satisfied, where Td (°C) is a highest temperature at which the steel sheet is annealed in the decarburization annealing and Tf (°C) is a highest temperature before secondary recrystallization of the steel sheet starts in the final annealing. reheating a steel slab in a temperature range of 1300 °C or less, the steel slab having a composition that contains, in mass% or mass ppm, C: 0.002% to 0.08%, Si: 2.0% to 8.0%, Mn: 0.005% to 1.0%, N: less than 50 ppm, S: less than 50 ppm, Se: less than 50 ppm, sol.Al: less than 100 ppm, at least one selected from: Sn: 0.010% to 0.200%; Sb: 0.010% to 0.200%; Mo: 0.010% to 0.150%; and P: 0.010% to 0.150%, and optionally at least one selected from: Ni: 0.010% to 1.50%; Cr: 0.01% to 0.50%; Cu: 0.01% to 0.50%; Bi: 0.005% to 0.50%; Te: 0.005% to 0.050%; and Nb: 10 ppm to 100 ppm, with a balance being Fe and incidental impurities; hot rolling the reheated steel slab into a hot rolled steel sheet; optionally hot band annealing the hot rolled steel sheet in a temperature range of 800 °C or more and not more than 1200 °C; cold rolling the hot rolled steel sheet once or twice or more with intermediate annealing in between, to form a cold rolled steel sheet having a final sheet thickness; performing decarburization annealing that also serves as primary recrystallization annealing, on the cold rolled steel sheet, wherein the decarburization annealing is divided into first and second stages, wherein annealing is performed in the first stage in a temperature range of 800 °C or more and 900 °C or less that eases decarburization, and annealing is performed in the second stage at a temperature which is higher than the temperature at which the annealing is performed in the first stage; applying an annealing separator to a surface of the steel sheet after the decarburization annealing; and performing final annealing on the steel sheet with the annealing separator applied to develop the secondary recrystallized texture and also to form a forsterite film, wherein a relationship Td ≥ Tf is satisfied, where Td (°C) is a highest temperature at which the steel sheet is annealed in the decarburization annealing and Tf (°C) is a highest temperature before secondary recrystallization of the steel sheet starts in the final annealing.