Power loss of Fe-3%Si grain-oriented silicon steel was measured after ball scribing with different spacing using a self-designed tool. Three different sections of power loss, including hysteresis loss, abnormal loss, and eddy current loss, were measured and calculated, respectively. The loss variation and ratio were analyzed based on the experimental data. At 1.0 T, hysteresis loss of tested steel with scribing spacing of 8 mm descends by 8.2% compared to samples without scribing, which is similar to the total loss variation, and abnormal loss descends by 16.8%. At 1.0 T, hysteresis loss ratio of the steel with scribing spacing of 16 mm ascends from 55.7% to 57.9%, and eddy current loss increases from 17.4% to 24.1%, while abnormal loss descends from 26.9% to 23.7%. The experimental results show that the reduction of power loss after scribing is mainly due to decreasing of hysteresis loss and abnormal loss.