A composite magnetic member configured so a nonmagnetic portion different from conventional ones is formed in part of a magnetic member and includes: a base portion including a mother material containing a ferrite phase; and a nonmagnetic portion having an austenite phase that is formed by solid solution of nitrogen (N) into a part of the mother material, the nonmagnetic portion having saturated magnetization less than that of the base portion. The nonmagnetic portion can be obtained by irradiating a high energy beam to a surface portion of stainless steel or the like while relatively moving the beam. This beam is near-ultraviolet nanosecond pulse laser having a short wavelength within a near-ultraviolet range and a pulse width of 10 ps to 100 ns. By adjusting the amount of N introduced and to form a solid solution due to the modification process, the nonmagnetization ratio of the member can be controlled.