In order to achieve accurate measurements of power line communication (PLC) module power, power measuring instruments solve common error is large, complex operation problems, design based on Labview PLC module power measurement system that user-friendly, easy to operate adjustable sampling rate and sampling period. The working principle of the measurement system, a detailed analysis of the calculation method of power; the same time, a variety of measurement systems are compared, analyzed experimental data obtained current system highly efficient and stable, high accuracy results. Finally, the causes of different types of measuring systems large errors were discussed, summarized the necessary conditions to ensure high precision and high sensitivity power measurements.