This paper presents the speed control of DC motor using six pulse controlled rectifier. The conventional Proportional Integral (PI) control is used for firing angle control. The armature current is fed back and compared with reference current representing desired speed values. The proposed system is simulated using SimPowerSystem and Control System Matlab toolbox. The time domain plot of reference and actual armature current are shown in results section. The results are satisfactory with deleterious effect on input current. The frequency plot of input current is provided to show the harmonic contents, generated as a result of control operation