Power line carrier communication technology utilizes existing power transmission networks for data transmission, which has the characteristics of low construction cost, fast and flexible deployment, and is widely used in local communication in local area networks. However, when the number of nodes is too large or the acquisition frequency is too high, each node will transmit data to the root node alone, which will bring huge amount of data to the entire communication system, and reduce the communication efficiency, affecting the real-time monitoring of the photovoltaic system. For this reason, aiming at the huge amount of data generated in the process of power line carrier communication, a data fusion algorithm of power line carrier communication based on minimum spanning tree transmission path is proposed to reduce the amount of transmission data and save the communication transmission resources, thus enhancing the transmission capacity of power line carrier access network. Finally, the proposed algorithm is proved to be effective by comparing the amount of data brought about by the fusion algorithm and the non-fusion algorithm.