Abstract: Yi Yi Ni Zhi (Tracing back Intent through Understanding) is a method that Mencius adopted when he explained the poem and criticized Xian Qiumeng’s misunderstanding of the poem Bei Shan. On account of his own Confucian stand, Xian Qiumeng obtained three aspects of understanding of the poem, namely text-centered understanding, context-centered understanding and expectation-centered understanding. The contradictions between the three aspects contributed to Xian’s out-of-context understanding of the poem. However, Mencius’ notion can only be regarded as one of interpretations simply because Yi Yi Ni Zhi (Tracing back Intent through Understanding) has the features of exclusiveness and uniqueness. Besides, the poem of Bei Shan is likely to be interpreted from more than one angle because of its unique structure. The “understanding” and “intent” in Yi Yi Ni Zhi convey Confucian doctrines of benevolence and righteousness, presenting two psychological premises: “the same mental structure” and “a mind intolerable of others' sufferings”. Mencius’ method of Yi Yi Ni Zhi showed that he used love extended from the ethic emotions to replace the feeling of resentment