A method of manufacturing a base unit of a spindle motor includes the steps of: defining a base plate including a support fitting portion; fitting a support to a hole portion passing through the support fitting portion; measuring an inclination of the support fitting portion; calculating a laser irradiation area and a laser irradiation output based on the inclination; irradiating the support fitting portion with a laser beam; and measuring the inclination of the support fitting portion again. The base plate is made of a metal, and is defined by press working, casting, or forging. The support is fitted to the hole portion by crimping, press fitting, or welding. This method reduces the inclination of the support fitting portion, thereby reducing a distortion of the support, which serves as a rotation center of an access portion.