Abstract: A Letter to the Scholar Hou Quan is written by Bai Juyi for his good friend as a gift.Apart from Mr. Fu Xuancong's quotation from it in his book 'Tang Dynasty Imperial Examination and Literature', it has attracted little attention of researchers. The paper points out that though Bai Juyi's work is less than 300 characters, it is rich in meaning, infinite for thoughts, which manifests author's great art expressive force in short length. Besides the rich connotation of literary style, it is exquisite in writing techniques and covers deep and broad social content. It has not only the strong esthetic value, but also the very good cognition value.