Disclosed is a brake disc for vehicles including a ring-shaped disc part provided with an insertion space formed at the central region thereof, a hub part disposed within the insertion space and provided with recesses formed on the external circumferential surface thereof, and connection parts configured to connect the disc part and the hub part, wherein each of the connection parts is divided into a curved section extending from the internal circumferential surface of the disc part and having both curved side surfaces and a rectilinear section extending from the curved section, having both flat side surfaces and inserted into each of the recess, and widths of the curved section and the rectilinear section are decreased in a direction toward the hub part.