A fitting method using parallel beam x‐ray diffraction (XRD) for profiling phase content changing with depth is presented. This method depends on measurements of XRD intensity at various incident angles, and numerical procedures are employed for obtaining the true depth profiles quantitatively. The procedures were then applied to a nitrided steel sample without preferred orientation and a thin‐film sample with preferred orientation. Both model‐independent and model‐dependent ways were used in fitting. ©1996 American Institute of Physics.