MR examination of 86 lumbar discs of surgically confirmed 42 patients were analysed retrospectively. Eighteen discs were bulging and 68 were herniation. Forty-eight herniations were protrusion type, 17 were extrusion and 3 were free fragment type. L4/5 discs were involved most frequently(35/86) and L5/S1(27/86), L3/4(15/86) and L2/3(8/86) were involved. The signal intensity of adjacent vertebral bodies were hypointense on T1 and T2 weighted images in 18 cases and hypointense on T1 weighted image and hyperintense on T2 weighted image in 13 cases. Thirty-one diseased discs showed hypointensity on both T1 and T2 weighted images. MR imaging showed excellence in the diagnosis of disc rupture. Eight of 10 ruptured discs were confirmed surgically. MR diagnoses of forty-seven(87%) discs of surgically confirmed 54 discs were accord with operation findings. However, CT was superior to the diagnosis of facet oint hypertrophy and ligamentum flavum thickening. W concluded that MR could be diagnostic imaging of choice in the evaluation of lumbar disc diseases.