In order to enhance the maintenance and management ability of the running watt-hour meter, based on the enhanced load control terminal, a construction project of watt-hour meter remote online detection system is proposed. Through the transformation, the existing load control terminal can realize time synchronization with the detected watt-hour meter, can read and output energy measurement pulse, and can obtain its own state information. With the newly developed watt-hour meter remote online detection software which fixed fault and alarm judgment criteria, the upgrade of existing energy metering automation system can be completed. Then a new watt-hour meter remote online detection system can be built with the enhanced load control terminal and the upgraded automation system. The test results carried out on the operation platform of the power supply office show that the system not only can detect the measurement performance of the watt-hour meter and correctly determine authenticity of watt-hour meter failure or abnormal alarm information, but also can diagnose the running state of the enhanced load control terminal. It can be seen that the system can significantly improve the operation and maintenance efficiency of watt-hour meter.