The LD-Ⅱ monitoring and positioning system of lightning of mining area was built to analyze thunder density of surface, polarity and amplitude of lightning current, thunder time and position of thunder point in mining area of Yanzhou Mining Group, and distribution of lightning nearby areas of high-voltage lines of mine was researched. A mathematical method was used to make simulation calculation for lightning of three typical towers and lines of the mine grid. Some measures were proposed to improve ability of lightning protection and lightning resistance of the mine grid based on statistical analysis and mathematical calculation, the measures were reducing grounding resistance of towers, using creepage adjustment and adding arrester. The actual application showed that the measures have certain feasibility.