A motor vehicle body is provided with a substantially vertical wall, which separates a lower zone of the passenger compartment from the engine compartment, and with a structure for receiving and draining water; such a structure protrudes forward into the engine compartment from an upper end of the substantially vertical wall and has an upper crosspiece shaped so as to define a manifold for receiving water; the upper crosspiece has a perforated intermediate portion and two opposite end portions provided with respective openings for draining water into drain passages; the structure further has a reinforcing crosspiece, which is arranged underneath the perforated intermediate portion for receiving some of the water and is shaped so as to define a channel which is elongated in the transversal direction so as to divert the water sideways and outwards.