To provide a filter device for control valve which secures wide effective area of a filter by securing a wide opening portion of a frame body when attached to a control valve.
A filter device 10 for control valve includes: a frame body 20 formed by bending both the end portions A, B to form an annular shape so as to face each other in a belt-like shape, and including a plurality of opening portions 25 provided in the belt-like shaped portion; a filter member 40 provided in the opening portion 25 of the frame body 20; an engaging claw 30 extended from one of both opposite side portions of both the ends A, B of the frame body 20; and a recess 35 provided in another side of both the side portions to allow the engaging claw 30 to engage. The recess 35 is formed in the side portion of the opening portion 25 of the frame body 20.