An impeller includes: a disk that has a disk shape and is configured to rotate around an axis; and a plurality of blades that are provided at intervals in a circumferential direction on a side of a surface of the disk toward a direction of the axis and extend to a rear side in a rotation direction as the plurality of the blades go toward an outer side in a radial direction. Each of the plurality of the blades has: a primary blade which extends to the rear side in the rotation direction as the primary blade goes from an inner side toward the outer side in the radial direction, and a secondary blade which is provided at intervals on a side in front of the primary blade in the rotation direction to correspond to the primary blade.