A thrust reverser for an aircraft bypass turbojet engine nacelle has a generally annular shape around an axis and includes an annular frame for securing deflection grids. The frame has a first frusto-conical wall widening in the downstream direction and including an upstream peripheral edge configured to be attached to a casing of the turbojet engine. A downstream peripheral edge of the wall extends in the continuation of the wall and secures the upstream ends of the grids. A second annular wall extends radially outwards from an outer frusto-conical face of the first wall. The first and second walls are integrally formed and the second wall has axial openings through which actuators pass.