Abstract: Water-maze and step-down method were used to test whether theanine would affect Mice’s learning and memorialcapabilities. The test turned out with the results that certain dosage of theanine would shorten the time to reach the final in thewater maze and reduce the mistakes as well. The theanine could also extend the time of memory so as to significantly lessen themistakes. Therefore, the conclusion could be made that the theanine could help the mice to improve their learning and memorialcapabilities.

Key words: theanine, learning and memory, water-puzzle, step-down