Immune reconstitution inflammatory syndrome is a common manifestation in human immunodeficiency virus (HIV)-positive patients infected with tuberculosis (TB). One of the unusual complications of this condition is the development of psoas abscess. We describe a case of immune reconstitution inflammatory syndrome (IRIS) in a patient with disseminated TB under treatment, HIV-positive with a low CD4 cell count, complicated by bilateral psoas abscess. Our patient presented with fever, abdominal pain, and lymphadenopathy, typical symptoms of TB-IRIS. Diagnosis was confirmed by surgical drainage of the abscess of the right iliac psoas muscle with detection of acid-fast bacteria on Ziehl-Neelsen staining and negative culture of purulent discharge. Treatment with prednisone was started in addition to continuation of antituberculosis therapy and antiretroviral therapy.