Abstract: Aim\ To explore the effects of hypertension on amnesia and its mechanism.\ Methods\ In renovascular hypertensive rat（RHR） amnesia was evaluated by water maze and changes in content of M 1, M 2 receptors in hippocampus was assessed by ELISA methods. Results\ There was serious amnesia in RHR, and the content of M 1 receptors in hippocampus decreased significantly.\ Conclusion\ Hypertension can induce demental,which might be due to the changes in content of M receptor subtypes in hippocampus.