Mycobacterium avium (M. avium) is an opportunistic intracellular pathogen causing chronic pulmonary disease in immunocompromised individuals, particularly in those with HIV/AIDS. Current treatments present challenges due to duration, antibiotic resistance and toxicity, creating a need for novel treatments. Glutathione (GSH), a key intracellular antioxidant, is depleted in immunocompromised individuals. This study evaluated the direct and intracellular antimycobacterial activity of liposomal glutathione (L-GSH) against M. avium. Furthermore, the minimum inhibitory concentration (MIC) and depolarization effects of L-GSH were also determined. Our results indicate that L-GSH has potent direct antimycobacterial activity against M. avium through membrane depolarization and reduces intracellular survival of M. avium in human macrophages. Given the established GSH deficiency in HIV-infected individuals and the clinical need for novel Mycobacterium avium complex (MAC) therapies with favorable safety profiles, these findings support further investigation of L-GSH as a host-directed therapeutic agent for HIV-associated M. avium infections.