Space electromagnetic docking technology has perfect application for on-orbit servicing, but the electromagnetic and geomagnetic torques it brings create disturbances to the docking attitude. Also, the problems resulted from nonlinearity and coupling properties exist in the attitude controller design of space electromagnetic docking. The combined method of feedback linearization andH_∞, extended state observer andH_∞was proposed to design robust attitude controller for absolute/relative dynamics respectively, and the mentioned problems are better resolved. The advantages and shortages of the two control strategies are compared and researched, and the feasibility of designed controllers is verified by simulation. From theoretical research and simulation verification, it is right to put forward that the two control strategies are feasible and have better robust performance to model parameter change and outer disturbance, and the strategy of relative attitude control design is better for its preferably using measure information and no state estimator needs to be added.