In an engine electromagnetic valve operating device (20), an intake valve (17) is opened and closed by means of a first electromagnet (21), which is fixed to a cylinder head, and a second electromagnet (22), which is pivotably supported on the cylinder head by a fixed shaft (38) so as to be capable of swinging, attracting a first attraction face (23b) and a second attraction face (23c) respectively of an armature (23) having one end pivotably supported on the cylinder head by the fixed shaft (38) so that it can swing and having the other end abutting against a stem (18) of the intake valve (17). In this arrangement, by changing the angle between the first and second electromagnets (21, 22) by swinging the second electromagnet (22), the amount of lift of the intake valve (17) can be changed freely. Furthermore, since only at least one of the first and second electromagnets (21, 22) needs to be made to swing and, moreover, it is unnecessary to move the position of the armature (23), it is possible to form the electromagnetic valve operating device (20) compactly.