Feedback controllers are designed by way of controlling the amplitude of limit cycle of coupled van der Pol oscillators. Bifurcation control equations of weakly nonlinear systems are obtained by using the approximate method, and relationships between the amplitude of limit cycle and the control gain are acquired, hence the amplitude of limit cycle can be controlled effectively. By using numerical method of solving ordinary differential equations, time displacement curves and limit cycle of the uncontrolled or controlled system can be found. The results obtained by approximate method and in numerical calculation are in good agreement. The method may be applied to other coupled van der Pol oscillators.