In a transport pipe having a first opening portion through which toner is fed in from a toner hopper and a second opening portion through which the toner is discharged to a development device, a transport screw in which a helical blade is formed on a rotational shaft is rotatably provided. The width of the first opening portion in the direction of the rotational shaft is greater than the pitch (L0) of the blade at the first opening portion, and, at the downstream end of the first opening portion in the transport direction, the pitch of the blade is switched from the pitch (L0) to a pitch (L1) which is narrower than the pitch (L0). In this way, the amount of transport of the toner from the toner hopper to the development device with the transport screw is stabilized.