Oriented electrical steel sheet and a manufacturing method thereof

In a method for producing a grain-oriented electrical steel sheet, grooves each having a given length and extending in a direction including a direction perpendicular to a transportation direction of the grain-oriented electrical steel sheet are formed at given intervals in the transportation direction by irradiating the surface of the grain-oriented electrical steel sheet with a laser beam while scanning the surface of the grain-oriented electrical steel sheet with the laser beam. Further, in the method for manufacturing a grain-oriented electrical steel sheet, the laser beam is a continuous-wave laser beam having a laser wavelength » of 1.0 µm to 2.1 µm, power density Pd [W/mm 2 ] which is obtained by dividing laser beam intensity P by a focused beam area S is 5×10 5 W/mm 2 or more, and the power density Pd [W/mm 2 ] and scanning speed V [mm/s] of a focused spot of the laser beam on the surface of the grain-oriented electrical steel sheet satisfy a relationship of 0.005×Pd+3000‰¤V‰¤0.005×Pd+40000.