This paper mainly introduces drilling of Hole ZKS001 in the silver polymetallic mine in the Sijiagou-Kuanping section, Xiaoshan District, Shan County, Henan. It is a straight hole with the design depth of 900m. The upper strata are hard, broken, with well developed fractures, serious leakage, and falling blocks. There were many difficulties in drilling in this zone such as low penetration rate, difficult coring, serious wear of drill bits, which resulted in drill pipe fractures many times during drilling. The drill hole is located at the intersection of the valley and gully with serious water gushing. Many mud interbedds are present between the borehole depth of 200m and 460m, which resulted in borehole diameter shrinkage. During drilling, due to improper handling of many drilling technical measures, drilling was difficult, and accidents often happened, delaying the construction period and increasing the construction cost, which should be taken as a lesson for future operations.