A vent valve, an integrated air pump comprising the vent valve and an electronic sphygmomanometer. An upper cover (1), a lower cover (3) and a elastic body (2) in the vent valve form an upper air chamber and a lower air chamber (a, b), and the two air chambers (a, b) are communicated with each other only through a vent hole (21) in the elastic body (2). A vent port (12) of the upper cover (1) is communicated with the upper air chamber (a) to form a normally-open one-way valve that is communicated with the outside, and the lower cover (3) and the elastic body (2) form a normally-closed one-way valve at the vent hole (21), the lower air chamber (b) being led to the upper air chamber (a) through the normally-closed one-way valve. When the air pressure in the lower air chamber (b) is greater than the air pressure in the upper air chamber (a), the elastic body (2) is deformed towards the upper air chamber (a) so as to block the normally-open one-way valve and open the normally-closed one-way valve. Therefore, the opening and closing of the normally-open one-way valve and the normally-closed one-way valve can be realized through elastic deformation of the elastic body (2), and the air intake function and the ventilation function can be realized. The vent valve is a pure mechanical structure, and no electric energy is consumed. Due to the small size, the integrated air pump comprising the vent valve is applicable to a wearable electronic sphygmomanometer.Font lobjet de cette invention un obturateur dair, une pompe à air intégrée et un tensiomètre électronique. Le couvercle supérieur (1) et le couvercle inférieure (3) de lobturateur dair forment avec un élastomère (2) deux chambres à air supérieure et inférieure (a, b), lesquelles entrent en communication moyennant un trou dévent (21) pratiqué sur lélastomère (2). Une ouverture (12) ménagée sur le couvercle supérieur (1) forme avec la chambre à air (a) un clapet de non-retour normalement ouvert sur lextérieur, alors que le
