“A Letter of Advising to Launch an Attack on Hebei” was proposed to the Emperor Wen of Sung by Hsieh Lin-yun before he was back home to the east during his days off. In the article, he advised a northern expedition to Hebei, and the full text was collected in the “Biography of Hsieh Lin-yun” in The Book of Sung. Its significance was undoubted. However, the article has never been seriously discussed by scholars. There are indeed some unsolved issues about the article, and some current comments on it have to be deliberated. Besides, Hsieh Lin-yun’s ambitions and military opinions are also revealed in this article. Therefore, I will make an effort to discuss this article from several aspects in this paper.