The invention relates to a technical process of a deep foundation pit type transmission line tower grounding construction device. When transmission line tower foundations are being established and a foundation pit is not backfilled, a graphite grounding strip is used as a grounding material, a section of the graphite grounding strip is used as a leading up wire, the head end of each leading up wire is connected with the graphite grounding strip, and the tail ends or the leading up wires are connected with grounding downleads preset on the top surfaces of the transmission line tower foundationsseparately, thereby completing the installation of the grounding devices. The graphite grounding strip is corrosion-resistant, non-rusting and easy to lay, the grounding resistance is stable, the installation process is especially applicable to places with acid and alkaline soils, difficult construction and high resistivity, the secondary young crop compensation fee and the land acquisition fee brought by secondary excavation are avoided, especially in regions with high compensation fees of grasslands, agricultural and forestry land and the like, and non-metallic fixtures are adopted for connecting the graphite grounding strip and leading up wires, thus the installation process is faster and more convenient.