B-1 cells, a subtype of B lymphocytes, are found in lymphoid tissues and peritoneal and pleural cavities. They play diverse roles, releasing cytokines, generating antibodies, regulating the immune response, engaging in phagocytosis, and moving to inflammatory sites. However, their physiology remains partially understood, especially in stressful conditions like sleep restriction. This study aimed to investigate murine B-1 cell activation and differentiation under sleep restriction. Male C57BL/6J mice underwent an 18-hour sleep restriction for 21 days, followed by Candida albicans or Paracoccidioides brasiliensis infection. Purified peritoneal B-1 cells were evaluated for activation markers, microbicidal molecules, cytokine gene expression, Toll-like receptors, and commitment factors. Results showed that sleep restriction minimally influenced activation marker expression in B-1 cells across infection models. However, under sleep restriction, microbicidal molecule production increased in P. brasiliensis (NO) and C. albicans (ROS) infections. Gene expression revealed elevated TLR-2 and cytokines (IL-12, IL-6, TNF-α) in sleep-restricted animals. Lineage commitment analysis indicated myeloid polarization in sleep-restricted B-1 cells for all infection models. These findings underscore the impact of sleep restriction on B-1 cell activation and differentiation, with outcomes varying based on infection type. This study highlights the importance of investigating immunological changes resulting from sleep restriction.