Sarcoidosis is a chronic disease characterised by the development and accumulation of granulomas in multiple organs. We report two observations of disseminatedMycobacterium genavenseinfection in patients with proven sarcoidosis. High fever and abdominal pain appeared at 8 and 18 months following the initiation of immunosuppressive therapy. Abdominal computed tomography scans of the patients showed diffuse mesenteric lymphadenitis and splenomegaly. The diagnosis was obtained on bone marrow specimens for both patients with numerous acid-fast bacteria at direct examination and positive specific mycobacterial identification by nucleic acid amplification test. Despite prompt antimycobacterial therapy, occurrence of complications (peritonitis post-splenectomy surgery and lung carcinoma) resulted in a fatal outcome for both patients. These cases highlight that opportunistic infections likeM. genavenseor other nontuberculous mycobacterial infections should be considered for long-standing immunocompromised patients with sarcoidosis.