A grain oriented electrical steel sheet has linear grooves for magnetic domain refinement formed on a surface thereof and may reduce iron loss by using these linear grooves, where the proportion of those linear grooves having crystal grains directly beneath themselves, each crystal grain having an orientation deviating from the Goss orientation by 10° or more and a grain size of 5 μm or more, is controlled to 20% or less, and secondary recrystallized grains are controlled to have an average β angle of 2.0° or less, and each secondary recrystallized grain having a grain size of 10 mm or more is controlled to have an average β-angle variation of 1° to 4°.