Abstract: Reliable handover of intermediate terminal guidance handover section of laser terminal guided mortar is a prerequisite for successfully capturing the target. In view of the uncertainty of shift handover space, the scope of the shift handover space and the influence of related factors on the shift handover space were studied. Firstly, based on the constructed trajectory model and jamming model with six degree of freedom, the constraint conditions of handover space were presented from the aspects, including the perspectives of ballistic constraint, seeker operating distance, field of seeker view angle and correction ability. Then, based on Monte Carlo shooting simulation and linear interpolation fitting method, a handover space boundary under the condition of uncontrolled full interference was established as the reference handover space, providing the limits of time, pitch angle, yaw angle, range, ballistic height and lateral distance. And the wind, initial velocity deviation and shooting angle deviation were selected as the influencing factors of space boundary. Through the simulation, the space boundary of shift handover was established under the condition of uncontrollable and eliminating wind, initial velocity deviation and shooting angle deviation respectively. Finally, simulation analysis was carried out. The results show that, among the main factors, wind is the most important one among the factors to have the influence on the spatial boundary of shift handover. The muzzle velocity deviation has great influence on the shift time, range and ballistic height of mortar ammunition. The deviation of firing angle can increase the shift time and range. According to the results, the muzzle velocity deviation and firing angle deviation should be reduced as far as possible, especially when the wind speed is small. In this paper, the establishment of the handover space can also provide the judgment criteria for the time when the guided mortar starts the laser terminal guidance. Only the laser terminal guidance works under the condition that the missile body parameters meet the handover space, the projectile can hit the target accurately.