K-Mg salt deposit is widely distributed in Gammon Province of Laos, which belongs to soluble solid K-Mg salt deposit, the ore seams mainly spread in Cenozoic paleogene salt bed and mainly with sylvite and carnallite. By the systematic analysis on the engineering geological characteristics of soluble solid K-Mg salt, a set of drilling construction technology in soluble solid K-Mg salt deposit was probed out. The study on coring and core protection, leakage prevention and the control and borehole sealing technology was presented.