Electromagnetic solenoid has movable core having end surface that is formed between inner circumferential surface and outer circumferential surface of movable core; and fixed core having end surface that is formed between inner circumferential surface and outer circumferential surface of fixed core and faces the end surface of movable core. Ring-shaped protruding portion is formed at least either one of the end surface of the movable core or the end surface of the fixed core. Protruding portion is provided at a position that is shifted to a radially inner circumferential side of the end surface. A length between apex and inner circumferential edge of protruding portion is shorter than a length between the apex and an outer circumferential edge of protruding portion.