In this paper, taking laser cladding coating on drilling tool surface in extreme environment as the research object, aiming at the friction failure of its surface in acid and alkali environment, and the tribological law of laser cladding coating under different pH value lubrication conditions is explored. Metallurgical coatings are prepared by laser cladding technology, the microstructure of coatings is observed, and the tribological properties of coatings under the different pH value lubrication conditions are studied. The results show that the coating is density, element distribution is uniform, and present good metallurgical bonding to the substrate. The main wear mechanism under different pH value and lubricating mainly adhesive wear and oxidation wear, and pH value has less influence on the friction coefficient of coating. The coatings present serious falling layer phenomenon due to corrosion and friction together on the alkaline environment.