One of the most important prognostic factors in LCP disease is the extent of epiphyseal involvement. Magnetic resonance imaging is considered to be the technique of choice for early diagnosis of Legg-Calve-Perthes disease. Gadolinium-enhanced spin-echo MR images were obtained after nonenhanced Tl-weighted(spin-echo) and T2-weighted(gradient-echo) images. Four different areas were identified in the femoral epiphysis(necrosis, regenerative, cartilaginous and normal fatty bone tissue). The histological evolution of LCP is well described by Catterall and others. Comparing their description with our MRI finding, we suggest classification of LCP into three phases: (I) necrosis, (II) regeneration(IIa-early and IIb-late) and (III) reossification and sequale. T2 weighted image was useful in the early stage and Tl weighted image was useful in the later stage for evaluation of involved extent of the disease. With MRI, we think that we can find out the stage of LCP more early and rationally, pathological factors more easily and appropriate time for operation exactly. we believe that MRI is more adequate method to decide the stage of LCP disease.