The filter module case includes a casing, a cap, a first layer, and a second layer. The casing has a cylindrical shape. The cap has a cylindrical shape and defines a passage providing communication between the inside and the outside of the casing and receives an end portion of the casing and is bonded to the casing. The first layer is closer to an end and faces an outer peripheral surface of the casing and the inner wall surface of the cap. The second layer is closer to the center and faces the outer peripheral surface of the casing and the inner wall surface of the cap. The casing and the cap have organic solvent resistance. The first layer is formed of a first adhesive with organic solvent resistance. The second layer is formed of a second adhesive that has an affinity for hard-to-adhere materials and has a higher elasticity.