Abstract: System for steering, about its axes of rotation, a moving body propelled by jet reaction, particularly a missile. The system (1) comprises two first flow deflectors (3, 4) of which one (3) is able to act exclusively on the outlet flow from one of the nozzles (17) of the moving body (M) which is provided with two jet nozzles (17, 18), and of which the other (4) is able to act exclusively on the outlet flow from the other jet nozzle (18) of said moving body (M), these two first flow deflectors (3, 4) interacting in such a way as to be able to steer the moving body (M) about two of its three axes of rotation, and a second flow deflector (5) which is able to act on the outlet flows from the two jet nozzles (17, 18), but on just one outlet flow at a time, so as to be able to steer the moving body (M) about the third of its axes of rotation.