The accepted radiographic method to determine cervical spinal stenosis is the direct measurement of the sagittal diameter of the spinal canal on the routine lateral view of the cervical spine. The reported normal and abnormal values for this measurement are inconsistent because of various methods of obtaining the roentgenograms and different body types which affect the size of the X-ray image. According to Pavlow, the ratio method of determining crevical spinal stenosis, in which the sagittal diameter of the spinal canal is divided by the sagittal diameter of the corresponding vertebral body, is independent of technical factor variables and is a reliable method for determining cervical spinal stenosis. In order to determine the Pavlov's ratio of normal Koreans, and compare it with that of radiculopathic group, we measured the diameter of cervicl canal in 47 normal persons(28 male, 19 female), and 32 patients( 9 male, 23 female) who had transient tingling sensation and radiculopathic symtom from the second to fifth decades. The results were as follows :1) The average Pavlov's ratio from C3 to C7 in normal Korean men are 0.906(0.70–1.13), 0.899 (0.070–1.13),0.948(0.70–1.67) and 0.948(0.67–1.17), respectively, and those of normal Korean women are 0.977(0.83–1.15), 1.021(0.83–1.13), 1.014(0.84–1.33) and 1.055(0.88–1.18), respectively. 2) The average Pavlov's ratio from C3 to C7 in radiculopathic Korean men are 0.88(0.65–1.12), 0.90(0.68–1.12), 0.95(0.79–1.12) and 0.95(0.78–1.06), respectively, and those of radiculopathic Korean women are 0.902(0.70–1.27), 0.905(0.69–1.27), 0.939(0.70–1.33) and 0.931(0.70–1. 18), respectively. 3) There are not statistically differences of the Pavlov's ratio between the control group and the radiculopathic group. 4) We believe that the Pavlov's ratio is an effective method in detection of cervical stenosis and is able to eliminate technical factor such as body position, target and object-to-film distanc.