Stair nosing profile, of the type intended for forming an edge at a covering for a stair (8), more particular a covering formed of panels (2-2A-2B), in particular floor panels, which, at least at one side, are provided with coupling means (3), characterized in that the stair nosing profile (1) is composed of at least two components, a first component (4) forming at least a portion of the nosing (6) of the stair nosing profile (1) and extending, away from the nosing (6) of the stair nosing profile (1), towards the rear with a portion (7) intended for being applied on top of the stair (8), and a second portion (5) forming a substructure for the first component (4), respectively, whereby the stair nosing profile (1), in the proximity of its rearmost extremity (9), is provided with coupling means (10) intended to cooperate with the coupling means (3) of the panels (2), and whereby these coupling means (10) are realized at least partially in the second component (5).