A toner supply container (1) detachably mountable to a main assembly (100) of an electrophotographic image forming apparatus includes (a) a toner accommodating portion (1n) for accommodating toner; (b) a toner supply opening (1g) for discharging toner accommodated in the toner accommodating portion; (c) a toner feeding member (2) for feeding the toner accommodated in the toner accommodating portion (1n) toward the toner supply opening (1g); (d) a sealing member (3) including a sealing portion (3b) for openably sealing the toner supply opening (1g). A driving portion drives the toner feeding member. The sealing member (3) has four functions which are (1) to seal the toner supply port portion (1a); (2) to receive the rotation force transmitted from the main assembly (100); (3) to transmit the rotation force to the feeding member (3); and (4) to engage with an engageable member (6) provided in the main assembly of the apparatus to open and close the toner supply port portion (1a). <IMAGE>
