A flexible, resilient respiratory mask facial seal adapted for confronting engagement with the face of a user to form an annular sealed interface encompassing a predetermined portion of the user's face. The facial seal includes a peripheral wall and an inturned flap seal. The flap seal projects radially inwardly of the peripheral wall and defines a contoured sealing surface adapted for confronting and sealing engagement with the user's face. The flap seal includes a recessed area corresponding substantially in the shape to a human nose for continuously and matingly conforming to the front and side contours of the user's nose when the facial seal is brought into confronting engagement with the user's face. The facial seal may be adapted for attachment to a respiratory mask body or may be removably placeable over the facial seal of an existing respiratory mask.