The invention provides a formation design and control method for a small celestial body defense formation satellite. Based on a small celestial body orbit deflection model, the search of the formation flight initial conditions is realized through a multi-target optimization algorithm, and the corresponding control method is designed for maintaining the formation. The method specifically comprises the following steps: the step one: defining the small celestial body orbit deflection distance; the step two: building a mirror reflection satellite induction thrust module; the step three: based on a formation satellite relative kinetic model, searching the formation flight initial conditions; the step four: designing the formation control method, and maintaining the formation; and the step five: through the simulation, evaluating the formation design and control effect of the small celestial body defense formation satellite. The method is capable of designing and controlling the formation of the small celestial body defense formation satellite, adapting the working requirement of the mirror satellite, guaranteeing the working efficiency of the satellite formation, and realizing the high-precision tracking to the small celestial body by the satellite formation.