In order to meet the stage-Ⅳ emission standard in China, a electric control system based on EPR (electronic pressure regulator) for the lean-burn turbocharging heavy-duty automotive CNG engine was developed. The configuration and control principle of the CNG supply system, the intake management system and the ignition system were analyzed. By comparing with the multi-points injection system and single-point injection system, the principle and advantage of the EPR were analyzed. The Experiment indicates that the maximal power and the maximal torque of the CNG engine are close to those of the original diesel engine, and the emissions meet the stage-Ⅳ emission standard in China.