The tribological properties of a tungsten disulfide solid lubricant film prepared by atomic layer deposition were investigated. The WS2 film was deposited using tungsten hexacarbonyl and hydrogen sulfide as precursors. The results showed that due to the incomplete reaction of tungsten hexacarbonyl, steady atomic concentrations of carbon and oxygen were detected throughout the WS2 film. The friction tests showed that in humid air the WS2 film exhibited good environmental robustness, and in dry nitrogen it exhibited a low friction coefficient, which decreased to 0.035 at a steady lubrication state. The formation of a transfer film on the counterface of a Si3N4 ball, and the reorientation with a few top (002) basal planes in the wear track were revealed.