Background: There are controversial reports about memory improving and memory impairing effects of epinephrine and propranolol (1, 2). Talley (2000) reported that epinephrine attenuated performance in rats that were deprived of food for 24 hours (1). On the other hand, there are evidence that propranolol didn’t impair performance in the water maze (2). Also, adrenergic systems have consistently been shown to be involved in memory processing and storage (3). Methods: Young male wistar rats were given daily injection of epinephrine (0.1 mg/kg, sc) (4) or propranolol (20 mg/kg, sc) (5) 30 min before training and co-administration of epinephrine (0.1 mg/kg) and propranolol (20 mg/kg).sham groups were received saline at the same volumes and conditions. A Y-maze apparatus was used for training. Results: The results showed that epinephrine enhances spatial learning in first (p<0.05), second (p<0.01), third (p<0.05) and fourth (p<0.05) days. Also propranolol impair memory in fifth day (p<0.001). On the other hand, Comparison between co-administered and epinephrine groups significantly decrease spatial learning in first (p<0.05), second (p<0.01) and fourth (p<0.05) days. But there wasn’t any significant difference between co-administered and propranolol groups. Conclusion: These findings indicate that propranolol impairs improvement of spatial learning caused by epinephrine via blockade of beta-adrenergic receptors and it seems that epinephrine exerts its spatial memory enhancing effects via beta-adrenergic receptors.