Leakage plugging in Ordovician limestone cave has been difficult, as for the large leakage channel dimension and the slurry retention difficulty, the plugging technology of chemical consolidation with positive charges has excellent properties such as good retention, high strength and micro expansion. The chemical consolidation plugging agent contains positive charges, which can produce electric adsorption with the negative charges on the surface of leakage channel to increase retention ability; the strength of cured consolidating material can reach up to 17MPa in 48h, and the consolidating material has micro expansive function, the expansive ability can reach 3.33%, the leakage channel can be completely filled and plugged. The thickening time can be adjusted according to the underground construction situation. The chemical consolidation plugging technology was applied in well TP187 in Ordovician limestone cave, where the leakage rate was reduced from total loss to 1～2m3/10min in 3 times of plugging, which met the requirements of continuous drilling. Chemical consolidation plugging technology is effective in cave section leakage.