The invention relates to a motor vehicle comprising a dashboard (T) separating an engine compartment (M) from the front of a passenger compartment (H) of the vehicle, a floor at the rear of the dashboard (T), at the bottom of the passenger compartment, and a device for thermal protection of the passenger compartment, the thermal protection device comprising thermal protection means disposed on the one hand below the floor (P) of the vehicle and on the other hand, on the engine compartment side, under the dashboard (T). The thermal protection means comprise a dashboard thermal screen (1) having a main panel (11) disposed along the dashboard (T) and a floor front thermal screen (2) disposed below the front of the floor (P) of the vehicle, the dashboard thermal screen (1) presenting a lower edge in two parts (12, 13) by which it corresponds by overlapping with the floor front thermal screen (2), a first upstream part among the two parts (12) being shaped as a deflector and a second downstream part (13) among the two parts extending the first part (12) by determining an overlap zone (132) with the floor front thermal screen (2) by extending above the front of this thermal screen (2).
