A disk brake including a mount member having a pin insertion portion integrally connected to a connection portion so as to outwardly protrude from an outer surface of the connection portion in a radial direction of a disk rotor. A tip of a pin insertion hole of the pin insertion portion is positioned at an inner side of a vehicle relative to an outer portion. Thus, it is possible to prevent a braking torque from affecting the pin insertion portion of the mount member. As a result, it is possible to prevent a slide pin from interfering with an inner wall surface of the pin insertion hole, thereby preventing a brake judder phenomenon from occurring during a braking operation.