<p>There is provided a centrifugal compressor having a diffuser structure in which airflow is unlikely to separate from a hub side wall surface on a hub side wall surface downstream side within a diffuser passage. In a centrifugal compressor provided with a diffuser passage 15 for recovering static pressure by slowing down discharged air from an outer circumferential end of an impeller that rotates within a housing 11, a hub side wall surface 15b of the diffuser passage 15 is provided with an inclined plane 20 that approaches toward a shroud side, in a position on a downstream side of a portion parallel with a normal line direction of a section surface of an impeller exit.</p>
