The present invention surely absorbs ink leaked from an atmospheric pressure introducing port using an ink absorber while achieving the miniaturization of an ink jet recording apparatus. An ink absorber housing is constituted of a fixing plate and a frame body which is formed on a periphery of the fixing plate and accommodates an ink absorber therein. Projecting ridges which project toward the ink absorber side and are brought into contact with the ink absorber are formed on an inner surface of the frame body thus increasing a holding force for holding the ink absorber in the inside of the ink absorber housing. Since the projecting ridges are brought into contact with portions of the ink absorber and resiliently deform the ink absorber, the deformation occurs partially and a deformation quantity is small. Accordingly, it is possible to increase the holding force for holding the ink absorber while preventing the large crushing of the small pores and the small interstices among the fibers in the ink absorber. In this manner, even when a multi-functional device is further miniaturized, it is possible to allow the ink absorber to surely absorb ink leaked from an atmospheric pressure introducing port.