In this paper we report the results of the studies concerning the addition of varying concentrations of molybdenum on physical, chemical and engineering properties of 43 grade ordinary Portland cement. The studies regarding initial and final setting time of cement, bulk density, compressive strength, microscopic and spectroscopic properties have been carried out and the result of these studies are presented and discussed. Different building products containing varying concentrations of added molybdenum were prepared and subjected to hydrologic environment to investigate the leaching behavior of molybdate ions. The efforts have also been made to establish a quantitative co-relation between the concentration of added molybdenum and the intensity of any effect in above properties of the cement. Also the possible fixation mechanism of molybdenum in cement is suggested. The X-ray diffraction analysis of molybdenum added cement sample was carried out and it was observed that the insoluble molybdenum is distributed in Portland cement in the form of powellite (CaMoO4).