Introduction: The haemostatic system can be significantly altered by haematological malignancies and their treatment. Abnormal haemostatic values can be detected in about 50% of advanced disease and these underlie the characteristic thrombotic and haemorrhagic diasthesis seen in these patients. Haemostatic indices in Philadelphia Positive and Negative Chronic Granulocytic Leukaemia Patients were investigated to determine their clinical relevance and possible association. Patients and Methods: Fifteen newly diagnosed Philadelphia positive (ph+ve) and 11 Philadelphia negative (ph-ve) CGL patients were studied longitudinally along with 20 healthy controls. Baseline blood samples were collected and analysed before commencing first cycle chemotherapy and after each successive cycle up to sixth cycle .Samples were analysed for haemoglobin concentration (Hb), leucocytes count (WBC), platelet count (PLT), prothrombin time (PT), activated partial thromboplastin time (APTT), plasma fibrinogen (PFC), and euglobulin lysis time (ELT) using standard techniques. Results were analysed statistically using Student’s t-test. Probability values <0.05 were significant. Results: Ph-ve CGL patients had significantly higher baseline levels of PFC and ELT compared to Ph+ve patients (P < 0.05). Ph+ve CGL patients with complete remission had a significantly lower baseline level of PFC compared to those without remission (P < 0.05). There were no significant changes in PFC and ELT in both groups after the 4th cycle of chemotherapy (P > 0.05). Conclusion: Philadelphia negativity may be a potential risk factor for increased thrombotic tendencies in CGL patients. PFC may be a useful predictive marker of haemostatic activation in these patients.