A brake disc capable of sufficiently absorbing thermal stress associated with thermal expansion and deformation of the braking section. The brake disc includes a mounting section for attachment to a wheel, a braking section located at the outside circumference of the mounting section for brake pads to be brought into sliding contact therewith, and a connecting arm section for connecting each of the plurality of mounting portions of the mounting section and the braking section. Connecting arms in the connecting arm section each extend from their respective ones of the plurality of mounting portions in one side direction different from the radial direction of the braking section to reach the braking section, and adjacent mounting portions are connected to each other at least through a connecting arm.