Autonomous rendezvous and proximity operations of satellites in formation are the most advanced technologies in space missions. This paper presents a formation flight control of the relative translational dynamics of satellites moving in circular orbits around the Earth. The relative dynamical model for this formation flying problem is derived in Hill's frame based on Clohessy –Wiltshire (CW) equations. A tracking control problem of relative translational motion between two satellites in a leader-follower scheme has been discussed using an intelligent PID controller. This controller is implemented in the linearized model while the follower satellite is actively controlled to perform the required movements to bring itself into the desired formation to the leader satellite. The gains of this controller are tuned using MATLAB genetic algorithm (GA) toolbox to enhance the performance of the system. The simulation results compare the performance of both traditional and intelligent PID that clarify good control precision and the effectiveness of the proposed controller (GA-PID) in solving the spacecraft formation problem.