The loss of long-wave antenna mainly comes from the ground loss resistance, and the loss resistance can beimproved by laying a buried ground grid directly below the antenna, and the radiation efficiency of the long-wave antenna can beimproved. However, due to the actual terrain, it is necessary to partially overhead the ground grid. In the paper, the full-wavesimulation calculation tool based on the method of moments is used to analyze the influence of partial ground grid overhead on theelectrical performance of a single tower umbrella long-wave antenna, which provides guidance for the implementation of long-waveantenna engineering and the maintenance and transformation of ground grid.