Acinetobacter baumannii has emerged as one of the most troublesome pathogens in healthcare settings. Its clinical significance has been propelled by its remarkable ability in acquiring resistance to almost all available antibiotics. Colistin (COL), an old antibiotic, has become the last resort of treatment for multidrug-resistant A. baumannii. Unfortunately, COL heteroresistance and COL resistance have been reported all over the world in A. baumannii. Being the first report of COL-resistant A. baumannii from our institution, we have tried to explore the prolonged stay in the ICU of the patient and also briefly reviewed the literature. However, well designed trials of new therapeutic approaches are certainly required.