A toner cartridge comprises an inner tubular container (4) having a toner discharge opening (422) and accommodating a toner; an outer tubular case (6) having a toner passage opening corresponding to the toner discharge opening (422), and being fitted into the inner tubular container (4) relatively rotatably; and a seal member (8) having a sealing portion (82) for covering the toner discharge opening (422), the sealing portion (82) being strippably bonded to the outer peripheral surface of the inner tubular container (4), and an action portion (84) formed as a continuum of the sealing portion (82) and having a front end part secured to the outer tubular case (6). The sealing portion (82) of the seal member (8) has a longitudinal bond portion (821) and a peripheral bond portion (823) defined along the surroundings of the toner discharge opening, and a cut groove (86) provided inwardly of the peripheral bond portion (823) at the peel start side end part thereof.