The invention relates to an autonomous orbit reprogramming method of a spaceflight aircraft. The method comprises the following steps that spacecraft state information is acquired; out-of-tolerance of an orbit is calculated according to the state information; whether reprogramming is performed is judged according to the out-of-tolerance situation, flying according to the normal default orbit is performed if the out-of-tolerance situation does not occur, and ballistic reprogramming is performed if the out-of-tolerance situation occurs; the minimum i value corresponding to an accessible target orbit parameter in an orbit parameter library is judged according to the order of priority, and the preselected orbit corresponding to the minimum i value acts as a new target orbit; and the aircraft is controlled to fly according to the new target orbit. The spaceflight aircraft is creatively enabled to have the autonomous orbit reprogramming capacity so that self-rescuing under the fault state can be realized, the expected target is completed under the fault situation and the economic loss can be reduced and the safety risk can be reduced; and the manpower and material resource cost can be reduced through the autonomous mode without depending on ground equipment and personnel.