A method of manufacturing a grain oriented electrical steel sheet with an insulating coating, comprising: a grain oriented electrical steel sheet; and an insulating coating provided on a surface of the grain oriented electrical steel sheet, wherein the insulating coating contains 1) at least one selected from the group consisting of Mg, Ca, Ba, Sr, Zn, Al and Mn; 2) Si, P, O and Cr, and wherein the insulating coating has an outermost surface that exhibits an XPS spectrum showing a Cr2p 1/2 peak and a Cr2p 3/2 peak, the grain oriented electrical steel sheet with an insulating coating being obtained by performing baking and plasma treatment in this order after applying a treatment solution to a surface of a grain oriented electrical steel sheet having undergone finishing annealing, wherein the treatment solution contains a phosphate of at least one selected from the group consisting of Mg, Ca, Ba, Sr, Zn, Al and Mn, colloidal silica, and a Cr compound, wherein a colloidal silica content in the treatment solution in terms of solid content is 50 to 150 parts by mass with respect to 100 parts by mass of total solids of the phosphate, wherein the Cr compound content in the treatment solution in terms of CrO 3 is 10 to 50 parts by mass with respect to 100 parts by mass of total solids of the phosphate, and wherein conditions of the baking in which a baking temperature T (unit: °C) ranges 800 ≤ T ≤ 1000, a hydrogen concentration H 2 (unit: vol%) in a baking atmosphere ranges 0 ≤ H 2 ≤ 230 - 0.2T, and a baking time Time (unit: s) at the baking temperature T ranges Time ≤ 300 are met, and wherein the plasma treatment is a treatment which includes irradiating the surface of the grain oriented electrical steel sheet after the baking with plasma generated from plasma gas containing at least 0.3 vol% of hydrogen for 0.10 seconds or more. a grain oriented electrical steel sheet; and an insulating coating provided on a surface of the grain oriented electrical steel sheet, wherein the insulating coating contains 1) at least one selected from the group consisting of Mg, Ca, Ba, Sr, Zn, Al and Mn; 2) Si, P, O and Cr, and wherein the insulating coating has an outermost surface that exhibits an XPS spectrum showing a Cr2p 1/2 peak and a Cr2p 3/2 peak, the grain oriented electrical steel sheet with an insulating coating being obtained by performing baking and plasma treatment in this order after applying a treatment solution to a surface of a grain oriented electrical steel sheet having undergone finishing annealing, wherein the treatment solution contains a phosphate of at least one selected from the group consisting of Mg, Ca, Ba, Sr, Zn, Al and Mn, colloidal silica, and a Cr compound, wherein a colloidal silica content in the treatment solution in terms of solid content is 50 to 150 parts by mass with respect to 100 parts by mass of total solids of the phosphate, wherein the Cr compound content in the treatment solution in terms of CrO 3 is 10 to 50 parts by mass with respect to 100 parts by mass of total solids of the phosphate, and wherein conditions of the baking in which a baking temperature T (unit: °C) ranges 800 ≤ T ≤ 1000, a hydrogen concentration H 2 (unit: vol%) in a baking atmosphere ranges 0 ≤ H 2 ≤ 230 - 0.2T, and a baking time Time (unit: s) at the baking temperature T ranges Time ≤ 300 are met, and wherein the plasma treatment is a treatment which includes irradiating the surface of the grain oriented electrical steel sheet after the baking with plasma generated from plasma gas containing at least 0.3 vol% of hydrogen for 0.10 seconds or more.