A flow generator comprising: a suction portion (21, 23) into which air is suctioned; a fan(130, 230) introducing the air introduced into the suction portion (21, 23) in an axial direction to discharge the air in a radial direction; a fan housing (150, 220) in which the fan (130, 230) is installed and which guides the air discharged from the fan (130, 230); and a cover (120, 290) surrounding the fan (130, 230) and the fan housing (150, 220), wherein the fan housing (150, 220) comprises: a housing plate (151, 221) supporting the fan (130, 230); a guide wall (153, 223) protruding from one surface of the housing plate (151, 221) to surround at least a portion of an outer circumferential surface of the fan (130, 230); a first fan passage (138a, 234a) provided between at least a portion of the outer circumferential surface of the fan (130, 230) and the guide wall (153, 223); a second fan passage (138b, 234b) which is disposed at a downstream side of the first fan passage (138a, 234a) and provided between the outer circumferential surface of the fan (130, 230) and the cover (120, 290) and through which the air passing through the first fan passage (138a, 234a) flows; wherein the air passing through the first fan passage (138a, 234a) flows to the second fan passage (138b, 234b); and a flow guide portion (160, 227) protruding from the one surface of the housing plate (151, 221) and disposed on an outer circumferential surface of the guide wall (153, 223), wherein the flow guide portion (160, 227) is configured to, together with the outer circumferential surface of the guide wall (153, 223), guide a flow of the air passing through the second fan passage (138b, 234b) through a discharge portion (25, 27) located on the outer circumferential surface of the guide wall (153, 223) to discharge the air passing through the second fan passage (138b, 234b). a suction portion (21, 23) into which air is suctioned; a fan(130, 230) introducing the air introduced into the suction portion (21, 23) in an axial direction to discharge the air in a radial direction; a fan housing (150, 220) in which the fan (130, 230) is installed and which guides the air discharged from the fan (130, 230); and a cover (120, 290) surrounding the fan (130, 230) and the fan housing (150, 220), wherein the fan housing (150, 220) comprises: a housing plate (151, 221) supporting the fan (130, 230); a guide wall (153, 223) protruding from one surface of the housing plate (151, 221) to surround at least a portion of an outer circumferential surface of the fan (130, 230); a first fan passage (138a, 234a) provided between at least a portion of the outer circumferential surface of the fan (130, 230) and the guide wall (153, 223); a second fan passage (138b, 234b) which is disposed at a downstream side of the first fan passage (138a, 234a) and provided between the outer circumferential surface of the fan (130, 230) and the cover (120, 290) and through which the air passing through the first fan passage (138a, 234a) flows; wherein the air passing through the first fan passage (138a, 234a) flows to the second fan passage (138b, 234b); and a flow guide portion (160, 227) protruding from the one surface of the housing plate (151, 221) and disposed on an outer circumferential surface of the guide wall (153, 223), wherein the flow guide portion (160, 227) is configured to, together with the outer circumferential surface of the guide wall (153, 223), guide a flow of the air passing through the second fan passage (138b, 234b) through a discharge portion (25, 27) located on the outer circumferential surface of the guide wall (153, 223) to discharge the air passing through the second fan passage (138b, 234b). a housing plate (151, 221) supporting the fan (130, 230); a guide wall (153, 223) protruding from one surface of the housing plate (151, 221) to surround at least a portion of an outer circumferential surface of the fan (130, 230); a first fan passage (138a, 234a) provided between at least a portion of the outer circumferential surface of the fan (130, 230) and the guide wall (153, 223); a second fan passage (138b, 234b) which is disposed at a downstream side of the first fan passage (138a, 234a) and provided between the outer circumferential surface of the fan (130, 230) and the cover (120, 290) and through which the air passing through the first fan passage (138a, 234a) flows; wherein the air passing through the first fan passage (138a, 234a) flows to the second fan passage (138b, 234b); and a flow guide portion (160, 227) protruding from the one surface of the housing plate (151, 221) and disposed on an outer circumferential surface of the guide wall (153, 223), wherein the flow guide portion (160, 227) is configured to, together with the outer circumferential surface of the guide wall (153, 223), guide a flow of the air passing through the second fan passage (138b, 234b) through a discharge portion (25, 27) located on the outer circumferential surface of the guide wall (153, 223) to discharge the air passing through the second fan passage (138b, 234b).