Background: Hypoxia is defined as the reduction of the normal oxygen supply. The hypoxia is traditionally classified as acute and chronic. Chronic hypoxia was classified into three subgroups: diffusion-limited hypoxia, hypoxemic hypoxia, and hypoxia due to a compromised perfusion of leaky micro vessels. Serious hypoxic-ischemic events are known to have an adverse impact on cognitive function.  Aim:  to review the evidence concerning the effect of chronic hypoxia on childhood cognitive outcomes including development and academic achievement. Materials and Methods: We used scientific websites such as PubMed, Google Scholar, and Research Gate to get related articles about this subject. Results: There were 15 articles included in this review including both research and review articles. Conclusion: It has been suggested that cognitive function including knowledge, attention, memory and Oxygen supply to the brain tissue may be decreased under hypoxia. Thus, brain desaturation and resultant biological process may be responsible for the impairment of cognitive function although the underlying mechanisms are still unclear