This study presents an exergetic and sustainability analyses to assess the perfor mance of a genuine medium scale turboprop engine (m TPE) used on the Unmanned Aerial Vehicle (UAV). The exergy efficiency of the engine is obtained to be 17.24% whereas the exergy efficiencies of the compressor, the combustor, the gas generator turbine, the gas generator turbine mechanical shaft, the power turbine, the power turbine mechanical shaft and the exhaust duct are found to be 87.21%, 52.51%, 98.53%, 98.60%, 97.40%, 98.00%, and 94.29%, respectively. From the viewpoint of thermodynamics, the combust or is determined to be the bad factor on the engine performance among the engine components. According to overall engine analysis, the environmental effect factor, exergetic sustainability index, sustainable efficiency factor and ecological effect factor o f m TPE are found to be 4.80, 0.21, 1.21, and 5.80, respectively.