A b s t r a c t -F o r the MR strips stabilized by the permanent magnet films, we numerically analyze the effects of the leakage field of the permanent magnet films on the bias angle in the MR films. Using the magnet films a s the domain control films, .magnetization rotation in the MR films at the track edges is suppressed by their leakage fields and will in turn decrease the effective track width. The decrease of the effective track width is thought to be due to the large leakage field especially at the track edges, so we examined some cases o f decreasing the leakage field at track edges. Among the cases, the effective track width was most effectively enlarged when the distance between the magnet films was widened compared with the spacing of the leads.