VALVE DEVICE

A valve device includes a body (11), a solenoid valve (12) accommodated in an accommodation hole (23) of the body (11), and a joint member (110) fixed to the body (11). The solenoid valve (12) includes: a sleeve (41) having a tubular shape and fitted in the accommodation hole (23), and including an introduction passage (66) and a delivery passage (68); and a valve element (71) configured to open and close the passages (66, 68). A U-seal (57) is disposed between an outer wall surface of the sleeve (41) and an inner wall surface of the accommodation hole (23). The body (11) has an attachment hole (80) that is located downstream of the delivery passage (68) of the sleeve (41) and opens on an outer surface of the body (11). The joint member (110) including a backflow reduction valve (122) is fixed to the attachment hole (80).