In order to acquire the accurate adjustment of the orbit shape and height of the detector, a new method of spacecraft continuous thrust control based on radial force equilibrium flight was proposed. The dynamic polar coordinate model of continuous thrust equilibrium flight was established, and the analytical orbit solution under special conditions was derived, the boundary conditions were further analyzed, and the control law of continuous thrust was given. Using this equilibrium flight control theory, the optimal control strategy for orbit capture can be constructed. Considering the thrust level of thrusters, the integrated adjustment of orbit shape, orbit height and orbit phase can be adjusted through one or more control processes. Numerical simulations show that the space gravitational wave detector with micro thruster can achieve high-precision orbit capture by using the orbit control method of equilibrium flight. This method has the advantages of analytical control process, small calculation, simple and practical.