A pump device includes a first pump, a second pump, and a casing. The first pump and the second pump are centrifugal pumps. The casing includes a first pump chamber in which the first pump is located and a second pump chamber in which the second pump is located. The first pump chamber includes a first bottom surface, a first side surface, a first inlet, and a first outlet. The first bottom surface is located on one side in the first direction with respect to a first motor of the first pump. The first side surface is connected to the first bottom surface and extends in the first direction. The first outlet is open with respect to the first side surface. The second pump chamber includes a second bottom surface, a second side surface, a second inlet, and a second outlet.