In order to investagate the sensitivity of GTL base oil and common extreme pressure antiwear agents,the additives of Zinc dialkyldithiophosphate (T203),tricresoll phosphate (T306),molybdenum dialkyldithiocarbamate (S-525),molybdenum amine complex (MOLYVAN 855),thiophosphate complex (T307),isobutene sulfide (T321) and synthetic ester (VANLUBE 7723) were mixed with GTL base oil respectively,and the maximum non-seizure load,wear scar diameter and friction coefficient of oil samples after single additive and compound additives were investigated by four-ball test rig.The results show that T307 and MOLYVAN 855 have the best extreme-pressure and anti-wear properties in GTL base oils.The combination of T203 and VANLUBE 7723 and T203 and MOLYVAN 855 significantly improves the extreme-pressure and anti-wear properties of GTL base oil,while the combination of T203 and S-525 has the best friction reduction effect.When T306 blends with S-525,T307 and T321 respectively,the extreme-pressure performance is similar.While the blending of T306 and T307 show good extreme pressure performance and good friction reduction and anti-wear effect.