Aim: To assess the antibiotic prescription, microbes and its resistance pattern in patients admitted to respiratory ICU. Methods: This was a prospective, observational study conducted in the Department of Anaesthesia, Vardhman Institute of Medical Science (VIMS), Pawapuri, Nalanda, Bihar, India, for 1 year. A total of 220 samples (Sputum, Pleural fluid, Pus, IT-Tube sample, Bronchial swab, Respiratory swab) of RTI patients were collected from Respiratory ICU. For identification of different microorganisms selective media were used in this study. Isolate the microorganisms with the help of primary and secondary identification and antibiotic sensitivity were performed. Results: Majority of the patients was male 63.18% and rest 36.82% was female. Gram negative organisms are detected in (66.82%), Gram positive organisms detected (21.36%), and no organism detected (11.82%) of the swab samples. Conclusion: Piperacillin-tazobactam was the most common antibiotic prescribed to patients with respiratory infection admitted to ICU. More than half of patients had resistance to the empirical antibiotic used in our ICU, highlighting the need for antibiogram for each ICU. Most of the patient had prior antibiotic use and had mainly gram negative organisms with high resistance to commonly used antibiotics.