A draught-excluder device with delayed actuation, adapted to be attached to the bottom edge of a door hinged to a frame, which device comprises an enclosure having therein: a seal adapted to sealingly interact with a sill and drive means acting on said seal to move it between a raised inoperative position and a lowered operative position; an actuator associated with said drive means to control actuation thereof as a result of the interaction with the frame as the door is being closed; delay means acting upon said drive means to delay operation thereof; wherein said drive means comprise a slide having an appendage with an end edge adapted for interaction with said delay means and operably connected to said seal; wherein said delay means comprise a movable element having a first substantially vertical counteracting surface which is adapted to act against the end edge of said slide when said seal is in the raised inoperative position, and a second slide surface inclined with respect to said first counteracting surface for causing snap release of said movable element from said end edge of said slide as well as delayed sliding of the latter and movement of said seal toward said operating lowered position; wherein said end edge is substantially flat and vertical; characterized in that said movable element is a pivoting lever that pivots on said enclosure about a substantially horizontal axis and has a proximal end portion with said first counteracting surface and said second slide surface, said actuator comprising a longitudinal elongate element and said lever comprising a substantially vertical stop member, said elongate element being adapted to contact said stop member upon actuation of said actuator to cause said end edge to move from said first counteracting surface to said second slide surface when the door is closed. a seal adapted to sealingly interact with a sill and drive means acting on said seal to move it between a raised inoperative position and a lowered operative position; an actuator associated with said drive means to control actuation thereof as a result of the interaction with the frame as the door is being closed; delay means acting upon said drive means to delay operation thereof; wherein said drive means comprise a slide having an appendage with an end edge adapted for interaction with said delay means and operably connected to said seal; wherein said delay means comprise a movable element having a first substantially vertical counteracting surface which is adapted to act against the end edge of said slide when said seal is in the raised inoperative position, and a second slide surface inclined with respect to said first counteracting surface for causing snap release of said movable element from said end edge of said slide as well as delayed sliding of the latter and movement of said seal toward said operating lowered position; wherein said end edge is substantially flat and vertical; characterized in that said movable element is a pivoting lever that pivots on said enclosure about a substantially horizontal axis and has a proximal end portion with said first counteracting surface and said second slide surface, said actuator comprising a longitudinal elongate element and said lever comprising a substantially vertical stop member, said elongate element being adapted to contact said stop member upon actuation of said actuator to cause said end edge to move from said first counteracting surface to said second slide surface when the door is closed.