Abstract: A powder transporting device includes: a circulation path that receives and accommodates a developer from multiple toner cartridges filled with the developer, and along which the accommodated developer is transported while circulating; a first supply port that allows the developer to be fed onto the circulation path; a transport path that merges with the circulation path at a portion of the circulation path upstream from the first supply port to allow the developer to be transported therealong into the circulation path; a second supply port through which the developer is fed to the transport path; a detector that detects the developer accommodated in the circulation path; a first transporter that transports the developer in the circulation path at a first transport speed; and a second transporter that extends along the transport path in the circulation path, and that transports the developer into the circulation path at a second transport speed higher than the first transport speed.