Nano-tungsten disulfide oil samples with different mass fraction were prepared by using nano-tungsten disulfide particles as additives of cryogenic cutting oil CTY-B.The effects of Span-80,sodium dodecyl benzene sulfonate and PEG-6000 as surfactant on the dispersion stability of the cutting oil were investigated,and the tribological property of nano-tungsten disulfide in CTY-B was evaluated by using a HRS-2M high speed reciprocating tribotester.The micromorphology and element composition of worn surface were characterized by using scanning electron microscopy and energy dispersive spectrometer,and the lubrication mechanism was analyzed.The results show that Span-80 has the best dispersion effect as surfactant on nano-tungsten disulfide particles.Nano-tungsten disulfide as additive can effectively improve the tribological properties of CTY-B,when the mass fraction of nanotungsten disulfide is 2%,the friction coefficient and wear scar width are reduced by 24.8% and 16.4% respectively compared with the base oil.During the friction process,nano-tungsten disulfide is easy to deposite on the concave surface to form a discontinuous protective film,which can reduce the damage of the contact surface and play a certain role in repairing.