Abstract： Objective:To observe the effects of hyperbaric oxygen（HBO）therapy on the cognitive function in rats with diabetic complications and depression（DD），and investigate the role of adenosine and adenosine A1 receptors（A1R）.Methods:A total of 48 healthy male SD rats were randomly divided into four groups using the random number table method：blank control group，rats with DD model group，HBO treatment group，and adenosine A1 receptor selective inhibitor（DPCPX）group，with 12 rats in each group. Morris water maze and open field experiments were used for assessing the learning and memory，spatial exploration ability，and excitability changes of rats.Results:After HBO therapy，the learning and memory，spatial exploration ability，and excitability of rats with DD were significantly improved（ P<0.01）. The adenosine A1 receptor selective inhibitor significantly inhibited the therapeutic effect of HBO（ P<0.01）。 Conclusion:HBO therapy can significantly improve the cognitive function of rats with diabetic complications and depression，and adenosine and adenosine A1 receptors play crucial roles in this process.