Chronic intermittent hypoxia (IH) is one of the hallmark features of obstructive sleep apnea (OSA) and adversely affects neurocognitive and behavioral functioning. However, how the duration of IH correlates with its deleterious effects remains unexplored. We aimed to assess the effects of IH over a prolonged period of time mimicking untreated OSA. Male C57Bl/6J mice were exposed to IH for 96 weeks. Sleep activity was acquired using a piezoelectric system. Novel object recognition (NOR) and the elevated plus maze test (EPMT) were conducted as measures of cognitive function and anxiety, respectively. Brain inflammation was evaluated by a panel of inflammation marker assays. All tests were performed after 16 and 96 weeks of IH exposure. After 96 weeks, sleep percentages during the dark phase decreased in both IH and room air (RA) compared to 16-week exposure (RA: