To provide a portable oxygen enricher that can be used even when a patient is at home and/or leaving home (including during traveling in a car or the like).

The portable oxygen enricher is equipped with a compressing means 105 to compress air taken through an air inlet, an adsorbing means to adsorb and remove a predetermined component except for oxygen in the compressed air in adsorption cylinders 108a, 108b, and a product tank to accumulate the concentrated oxygen from which the predetermined component is removed. The inner face of a chassis is at least partially formed of a nonwoven fabric comprising polyolefin fibers having a fiber diameter of 1 to 4 m and polyolefin short fibers having a fiber diameter of 20 to 30 m.