Abstract: Cancer, particularly leukemia is one of the major causes of death amongst the cancer patients. So solving the mystery behind underlying causes and abnormalities that leads to the leukemia has become a challenge for he researchers. Again in each type of the leukemia, which kind of the biological marker is associated is a puzzle. Biological marker and tumour markers are measurable biochemicals that are associated with a malignancy. A wide range of these biological markers known as cluster differentiation (CD markers) markers have been found to be associated with leukemia. These include the Cd2, CD5, Cd7, CD10, CD20, CD33, CD34, etc. The expression of all these CDs has been associated in different types of leukemia. So, studying the level of expression of these different CDs can be a major breakthrough in the treatment strategies of leukemia.