Compressor inlet air-cooled gas turbine power plants are operational in various parts of the world where its performance is penalized by higher ambient temperature. Evaporative inlet air cooling is one of the simplest of the compressor inlet air cooling methods. In this paper effect of evaporative inlet air cooling on thermodynamic as well as emission performance of a basic gas turbine cycle has been analyzed. Apart from the impact of equivalence ratio, residence time, turbine-rotor-inlet temperature and compressor pressure ratio, the effect of relative humidity on emission performance has also been analyzed. The overall exergy destruction, NOX, and CO emission have been observed to be lower in case of inlet air-cooled cycle. For a fixed value of compressor pressure ratio, equivalence ratio, residence time and turbine-rotor-inlet temperature, the primary-zone-temperature, NOX, and CO emission increases with increase in relative humidity whereas UHC emission decreases. Hence, inlet air-cooled gas turbine cycle based power stations may have immense potential both in terms of thermodynamic performance as well as in terms of emission characteristics in geographical regions where ambient air humidity is lower.