A 56-year-old previously healthy female presented with chronic productive cough and fever. Chest X-ray revealed right middle lung opacities. Sputum acid fast bacilli smear was positive, however polymerase chain reaction was negative for Mycobacterium tuberculosis. Further investigations were pursued, which identified Mycobacterium asiaticum. Appropriate therapy with isoniazid, rifampin and clarithromycin for total 18 months (including pyrazinamide and ethambutol for first 4 months) resulted in clinical and radiographic improvement. Recognition of the possibility of this rarely described pulmonary pathogen is essential for successful treatment.