To meet the complicated control requirement of Biped robot with heterogeneous legs (BRHL), the master-slave dual-leg coordinated control strategy was adopted to simplify its planning scheme, of which the key of coordination is gait tracking control. Bionic knee joint enables the robot to walk more like human, but its modeling is complex and the control of bionic leg to track artificial leg is difficult. The P-type open/closed-loop iterative learning control (ILC) is therefore put forward to combine together the merits of open-loop and closed- loop ILC without a model to rely on so as to fit the control of gait tracking for complicated biped robot system. Experimental results demonstrate the correctness and effectiveness of the proposed coordinated control scheme.