Most of the low temperature solid lubricants have low wear resistance and high fluctuating friction coefficient at high temperatures and, in addition, high temperature solid lubricants create wear debris at low temperatures. Thus, there is a need for such lubricant coatings that can be used at a wide range of temperatures with sufficient wear resistance. Therefore, in this research, nanostructured composite coatings consisting of a hard Cr 2 O 3 ceramic matrix with silver lubricant particles were produced by atmospheric plasma spray (APS) process and their properties were evaluated. First, for the formation of ceramic matrix nanostructured coatings, Cr 2 O 3 nano particles were produced by 30 hr mechanical milling in attrition mill. Then, a well dispersed and stable aqueous dispersion including Cr 2 O 3 -Ag nanoparticles (with volume percentage of Ag, 0, 2, 5, and 10%), suitable for spray drying, was produced by horizontal mill with zirconia balls. The suspension was agglomerated to a nanostructured composite powder (particle size, 30-80 µm) by centrifugal disk atomizer spray dryer. Finally, Cr 2 O 3 -Ag nanostructured composite coatings were produced on a NiAl bond coat on steel substrate by atmospheric plasma spraying technique (APS). For development of bimodal structure coatings consist of both molten particles (microstructure) and semi molten particles (nanostructure) in APS, the plasma spray condition of nanostructured coatings was so adjusted that part of nanoparticles were not melted in the plasma jet. The characterization of coatings performed using x-ray diffraction, scanning electron microscope, energy dispersive spectroscopy, microhardness indentation and surface profilemeter. The results showed that, in spite of growth of crystallite size and the decrease of internal lattice strain of nanoparticles in nanostructured coatings, the crystallite size of these coatings was still lower and their internal lattice strain was higher than conventional coatings. Furthermore, due to existence of semi molten nanostructured particles in the microstructure of coatings, microhardness and fracture toughness of nanostructured coatings were lower and higher than conventional coatings, respectively. The tribological assessment of the coatings was so designed to simulate the working condition of high temperature moveable devices in aerospace application. For this reason the tribological tests were done by a pin-on-disc wear tester under the condition of 10 N load, linear velocity of 0.3 m/s, temperature of 25, 300, and 500°C and WC ball counterface. At all three test temperatures, neither weight loss nor a characteristic wear mechanism was observed on wear tracks. The results indicated high wear resistance of Cr 2 O 3 matrix plasma sprayed coatings. Moreover, both two evaluated factors in this research, the nanostructure processing and the presence of Ag lubricant particles, lead to decrease in friction coefficient, by reducing the brittleness of Cr 2 O 3 coating and formation of Ag thin film on contact surface, respectively, in all three test temperatures. Among the evaluated coatings, Cr 2 O 3 -5%Ag nanostructured coating had the best frictional behavior at 25, 300, 500°C temperatures. Keyword Chromium oxide, Silver, Friction behavior, Solid lubricant, Coatings, Plasma spray, Nanostructure