In this study, MoS 2 nanosheets have been prepared and treated ultrasonically with silver ammonia solutions. The MoS 2/Ag precursor was reduced using dopamine (DA) as reducing and linking agent at room temperature, and it was subjected to a hydrothermal treatment to produce MoS 2/Ag nanocomposites (denoted as MoAg). The MoAg samples were functionalized with N-oleoylethanolamine to improve dispersion in the base oil component of additives. Use of the functionalized MoAg (denoted as Fc-MoAg) as a lubricant additive for steel balls resulted in effective friction reduction and anti-wear. This work avoids ion exchange during exfoliation, and the Ag + has been reduced to nano-silver particles by dopamine to enlarge the layer spaces of MoS 2. Taking the case of lubrication with base oil containing Fc-Mo 0.6Ag 15, the wear scar diameters and coefficients of friction of the steel balls were 0.428 and 0.098 mm, respectively, which were about three-fifths base oil. In addition, MoS 2/Cu and MoS 2/Ni nanocomposites were synthesized and the tribological properties associated with steel/steel balls assessed. The results demonstrate that all MoS 2/metal composites exhibit enhanced tribological behavior in the steel/steel pair tests. Both nanocomposite synergy and the tribofilm containing sulfide, oxide, carbide, and other compounds play important roles in achieving reduced friction and improved anti-wear. The friction and wear properties of base oil containing Fc-MoAg and commercial additives were evaluated using a four-ball wear tester with steel/steel, steel/zirconia and zirconia/zirconia pairs. The base oil containing Fc-MoAg delivered smaller coefficients of friction (COFs) and/or scarring groove depths than those observed with the use of pure base oil and base oil containing commercial additives.