A toner cartridge comprises a toner container which contains toner, a driving member which rotationally drives a conveying member, an agitating member which agitates a toner in the toner container while being rotated, a driven member which rotates in association with the driving member which is for rotationally driving the agitating member, and a rotational body which rotates according to rotation of the driven member, has a plurality of slits in rotational circumference for identifying a type of the toner cartridge, and has 1/K or more of the slits when a ratio of a rotational speed R1 (rad/s) of the driving member and a rotational speed R2 (rad/s) of the driven member is K=R2/R1.