Abstract: Since highly deviated wells and extended reach wells often involve high friction resistance in during drilling, large amounts of conventional lubricants are required, and the lubrication performances are often unsatisfactory. In order to solve the problems, the high-efficiency JZLu-1 lubricants were developed by using a synthetic base oil, together with spherical nano SiO2 and sulfur-phosphorus-molybdenum anti-abrasion extreme pressures agents, where it was then emulsified by a cationic emulsifier. Potentials, wear-resistance and lubrication performances under extreme pressures were determined by using a ζ potential analyzer, a four-ball tester and an extreme-pressure lubrication performance tester. In addition, electronic microscopes were also used to observe absorption of JZLu-1 on metal surfaces. Research results showed that the lubricant JZLu-1 had a weak positive charge, and may positively attach themselves to metallic surfaces to generate oil films; nano SiO2 contained in JZLu-1 may provide satisfactory wear-resistance performances, whereas sulfur-phosphorus-molybdenum extreme pressures agents may significantly enhance lubrication performances, with lubrication coefficient of 0.028 3 under extreme pressures. Application results of six wells indicated that the JZLu-1 high-efficiency lubricant could dramatically lower drag and torques in highly deviated wells or extended-reach wells, so as to eliminate problems of poor performances and large volume of conventional lubricants required in such wells.