High temperature solid lubricants are required for use on silicon nitride bearings with application temperatures of 600 degreesC and beyond. In the present research, the tribological properties of cesium oxythiomolybdate (Cs2MoOS3) thin films grown via pulsed laser deposition were studied as a function of temperature from 25 to 800 degreesC. When deposited on SO, the coefficient of friction, mu, was 0.03 at 600 degreesC. When deposited on Al2O3, ZrO2 and Inconel, mu=0.15 at 600 degreesC. The friction coefficient generally increased with decreasing temperature. Wear rates were low on all substrates between 400 and 600 degreesC. Friction remained low up to 750 degreesC on Si3N4 substrates, but failure occurred above 750 degreesC. The tribomechanisms are discussed.