In large air compressor installations consisting of multiple compressors operating continuously, even a small reduction in the inlet air temperature can improve the plant efficiency. Exergy efficiency is more rational than energy efficiency, and exergy analysis is more helpful than energy analysis for locating and evaluating available energy-saving potentials, identifying opportunities for improvements in system design, and establishing cost-effective system maintenance programs. When exergy analysis is performed on a system, thermodynamic imperfections can be quantified as exergy destruction, which represent losses in energy quality. In the present study, a thermodynamic analysis is made on the inlet air cooling system employed in a centrifugal compressor. Exergy input rate, exergy output rate, exergy loss rate, exergy destruction rate, and exergy efficiency were calculated with five different dead state temperatures and five different dead state relative humidities. Sustainability assessment is done by estimating the sustainability based on exergy efficiency.