The problem of the equal quality collinear threecraft Coulomb formation configuration control is studied. Thanks to the complexity of the relative motion dynamics of the threecraft Coulomb formation, the idea of using the tethered formation model is proposed to establish the equal quality collinear threecraft Coulomb formation. Considering the characteristics of dynamics model and the uncertain factors of the external environment, based on the nonlinear dynamic model which has been established, we design the synovial feedback control law for equal quality collinear threecraft Coulomb formation in geosynchronous orbit. The feedback linearization is added in the synovial mode control to increase the stability and veracity of the controller, and to ensure robustness of formation. Simulation shows the method can make formation to desired configuration with favorable control performance.