Abstract:According to the broken, leaking, clasping and block falling limestone formations of the bauxite in Guizhou, the combined drilling technology of drilling with casing and wire-line coring was used to overcome the difficulties of conventional drilling methods, ZK3369 hole drilling was successfully completed with good result. On the basis of the analysis on the construction difficulties, the paper introduces the combined drilling technology of drilling with casing and wire-line coring in the broken, leaking, clasping and block falling formations.