In this experimental paper, the judder vibration of automotive disk brake was analyzed by the finite element method and compared with experimental results. The relationship between specific modes of disk and pad, and hot spot was investigated. Characteristics of the judder vibration were measured by using the chassis-dynamo and hot spots were photographed by highspeed infrared camera. Vibration modes of the brake disk and pad were measured and an specific relationship between mode shapes and hot spots was found. Results show that the judder vibration occurred due to the frequency modulation of the specific mode frequency of disk brake due to the non-linearity phenomenon. This relationship was examined by the frequency analysis of the judder vibration.