The physico-chemical analysis of ground water quality of Ajmer city in Rajasthan is presented in this paper. It is important from this point of view to observe the suitability of water for safe drinking and irrigation. The different parameters measured are calcium hardness, magnesium hardness, total hardness, As3+, Cd2+, Pb2+, Hg2+, TDS, F–, Cl–, NO3 –, SO4 –2 alkalinity, carbonate hardness, pH and conductivity. From the observed data it is found that parameters like conductivity, TDS, F–, NO3 – and hardness are higher in concentration from prescribed values. From the analysis of ground water quality, it is observed that some of the sites are not suitable for drinking purpose as well as domestic purpose.