With the advancement of smart grid construction, power line high-speed carrier communication technology has been widely applied in power consumption information acquisition systems. High speed carrier communication units with superior performance and strong reliability have become the key to ensuring the efficient operation of power consumption information acquisition systems. In order to provide a comprehensive and standardized measurement of the performance of high-speed carrier communication units, this article conducts research on the performance testing technology of high-speed line carrier communication units, proposes the software scheme and hardware architecture of the testing system, and takes power spectral density testing as an example to explain the process of performance testing in detail. Finally, the power spectral testing results of the carrier communication unit are analyzed to verify the effectiveness of the constructed testing system.