Imatinib mesylate is a promising drug used for targeted therapy in chronic myleiodleukemia. As with any other anticancer drugs, this drug too leads to immunosuppression in the patients which may cause severe infectious diseases. Generally preferred antibiotic class in this case is fluoroquinolones and moxifloxacin being one of the advanced new generation flouroquinolones having wide range of antimicrobial activity, it is frequently used along with Imatinib mesylate. When these two drugs are used for chronic myleiodleukemia patients, there is a need for an accurate and precise analytical method for their proper therapeutic drug monitoring and in quality control. In the literatures, there are no methods available to simultaneously analyse these drugs by any analytical techniques. Thus, an attempt was made to simultaneously estimate Imatinib mesylate and moxiflxacin hydrochloride by using Ultra High Performance Liquid Chromatography technique. The developed method was subsequently validated as per ICH guideline for its accuracy, precision, linearity, specificity, and robustness. The developed analytical method would be very useful for quality control laboratories in the pharmaceutical