A developer supply container is mountable to a developer receiving apparatus including a driving gear, wherein the container mounted to the apparatus is settable to a set position by a rotating operation of the container in a setting direction by an operator, and includes a substantially cylindrical portion; a developer discharging opening provided on a surface of the cylindrical portion; a developer feeding member provided in the cylindrical portion; a drive receiving member to engage with the driving gear for rotating the developer feeding member; and a regulating portion for regulating a mounting attitude of the cylindrical portion so as to prevent engagement between the drive receiving member and the driving gear. A rotating operation of the cylindrical portion toward a set position about a center of the cylindrical portion in a setting direction engages the drive receiving member with the driving gear.