Fluid film bearings are widely used for HDD spindle motor. Recently, HDD is required to improve shock resistance because of using many mobile devices such as mobile PCs, portable audios and car navigation systems etc. Therefore, in the manufacturing of the spindle motors, designing parameters for fluid bearings are important to decrease vibration displacement of the bearings. Moreover, it is necessary to comprehend dynamic characteristic of the fluid film bearings to improve its problem. The oil film coefficients, spring and damping coefficients, are analyzed theoretically. However, so far, experimental research has been limited because the spindle consists of a pair of upper and lower bearings. In this paper, we describe a method of identification for oil film coefficients experimentally. At first, we measured the displacement response of the fluid film bearing vibrated by disturbance, after that conducted curve fitting to identify the oil film coefficients.