Backround: Chronic myelogenous leukemia (CML) is a myeloproliferative neoplasm that originates in abnormal pluripotent bone marrow stem cell and is associated with the BCR ABL1 fusion gene located in the Philadelphia chromosome. Objective: Molecular diagnosis is done by detecting BCR-ABL fusion transcripts which is also helpful in the identification of various molecular subtypes on the basis of breakpoint cluster regions involved in the translocation. Materials & Methods: This was a data based study & a total of 90 patients were enrolled in the study. The molecular diagnosis was done on Real Time PCR in a stepwise manner using commercial kits. Firstly RNA was extracted from blood kits, then cDNA was synthesized which was subjected to quantitative PCR & the BCR-ABL/ABL ratio was calculated. Results: Out of the 90 patients who reported with mild to moderate leucocytosis Philadelphia chromosome was not detected in 14 patients, 18 patients were with negative BCR-ABL/ABL ratio and 58 patients were found to be positive with mean value of 36.17±7.43 of the ratio which decreased with the treatment. Conclusion: Molecular detection of the BCR-ABL/ABL ratio is an important tool for assessing response to therapy and in developing more effective therapeutic modalities.