To provide a spindle motor capable of increasing reliability and reducing a manufacturing cost for the same by simplifying the structure of a rotational load measuring device.

The spindle motor 100 includes: a cylindrical case 110; a motor 120; a base end rotating body 130 capable of integrally rotating with the motor 120; a distal end rotating body 140 capable of integrally rotating with the base end rotating body 130; a drilling tool grip portion 150 capable of integrally rotating with the distal end rotating body 140; a rotational force transmission member 160 for transmitting the rotational force of the base end rotating body 130 to the distal end rotating body 140; and the rotational load measuring device 170 employing a capacitance measuring method for measuring the rotational load based on torsional deformation of the rotational force transmission member 160.