a container body having a toner filling port;

a cylindrical portion provided around the filling port; and

a detachable cap that closes an opening of the cylindrical portion, wherein

the cap includes:

a pair of claw parts provided deformably in a radial direction of the cylindrical portion and insertable into the cylindrical portion to be engaged with an edge of the filling port;

a link piece connecting tip ends of the claw parts;

a disk part having an opening;

a closing plate capable of closing the opening of the disk part; and

a fixing member which fixes the closing plate to the disk part, wherein

the closing plate is fixed to the disk part with the fixing member and the claw parts are engaged with the edge of the filling opening, so that the opening of the cylindrical portion is closed by the closing plate, and

the closing plate is detached from the disk part by detaching the fixing member, the link piece is pulled through the opening of the disk part to deform the claw parts radially inward to release engagement of the claw parts with the edge of the filling port, and then the cap is detached from the cylindrical portion, so that the container body and the cap can be reused.