Impact of health care on the population health has been measured in terms of morbidity and mortality but this measurement doesn’t distinguish between children, adults and the elderly. It does not also take into account the losses that occur because of handicap, pain, or other disability. Therefore, measures of population health which combine information on mortality and non-fatal healthboutcomes to represent the health of a particular population as a single number was introduced. QALYs and DALYs are both common outcome measures in economic evaluations of health interventions. QALYs is the comprehensive measure of health outcome because it can simultaneously capture gains from reduced morbidity (quality gains) and reduced mortality (quantity gains) and combine these into a single measure. DALYs is primarily a measure of disease burden where it combines losses from premature death and loss of healthy life resulting from disability. Although QALYs and DALYs are almost similar in their basic concept but there are few distinct differences which must be paid attention to in order to correctly utilize these measures.