As the construction of transmission lines increasingly extends to deep mountains and ridges, the research on mountainous micro-pile drilling rigs and transmission line micro-pile foundation construction technology has become increasingly important. This article discusses the characteristics of mountain micro-pile drilling rigs in the construction of micro-pile foundations for transmission lines and its application in mountain construction. The article introduces the structure and working principle of the mountain micro-pile drilling rig, and analyzes its adaptability in different environments. In addition, the article also elaborates on the construction technology of micro-pile foundation for transmission lines, focusing on the construction process of micro-pile foundation based on the down-the-hole mountain micro-pile drilling rig. This research provides valuable ideas and methods for the construction of mountain transmission lines, and has certain theoretical and practical value for improving construction efficiency, ensuring project quality, and saving costs.