Aiming at a kind of adjustable oil film bearing in highspeed roll grinder, its structural characteristics and working principle are analyzed. On these bases, finite element modal (FEM) analysis models of the bearing aimed at different adjusted positions were built, and the former 6 orders of natural frequencies were calculated, furthermore, the former 6 orders of modal shape images were also gained. Analysis results show as follows: bearing body is the vibration vulnerable area of the adjustable oil film bearing, and easy excited frequency region of the bearing body is 2 300~3 000 Hz. Therefore, the bearing should keep away from the easy excited frequency region in the course of practical working, and vibration resistance performance of the bearing body should be also enhanced as much as possible.