Abstract: A waste-disposal device for use with a bag unit of the type having an annular component from which a free end of tube extends to form a bag. The waste-disposal device comprises a bin having an open top end for accessing an inner cavity of the bin. A support is in the bin adjacent to the open top end and adapted to support the annular component of the bag unit for waste to be received in the bag of the bag unit extending in the inner cavity of the bin, by passing through a central opening thereof. A closing mechanism comprises a door pivotally connected to the support by at least one pivot and an abutment surface in the bin, a pivot axis of the at least one pivot being located at a same height or higher than a bottommost edge of the annular component of the bag unit when received in the support and when the bin has a bottom thereof on the ground.