A trash bag liner retaining and air venting device is attachable to a trash receptacle. The device includes a rim adapted to being removably secured to a top of a trash receptacle such that an upper region of a flexible liner is drapable thereover. A locking ring is provided which receives the rim in nested relationship and thus captures the liner therebetween. Preferably, an integral hinge joins the rim and the locking ring so that the latter is capable of pivotal movements relative to the former. Thus, the locking ring and the rim are movable into and out of engagement with one another to respectively positionally capture and release the liner.