An air inlet module incorporating, in one structural unit, on the one hand, a supply manifold, on the other hand, an exhaust gas reinjection circuit and, finally, a gas/liquid heat exchanger designed to cool the exhaust gases, the module consisting of a sealed assembly of at most four parts, namely, a first part comprising the inlet manifold, the outlet manifolds, a portion of the supply conduit, and a hollow body forming the tank of the exchanger, a second part comprising the many circulation manifolds and a support body for assembling said manifolds in the tank, and a third part of which one portion forms a cover for the hollow open container and comprising several conduit portions forming at least partially the exhaust gas circulation circuit and conveying these gases to the inlet manifold, also incorporated in said third part.