Kindness is the head of four-terminal heart, and it occupies an important position in Mencius's thought. For this reason, by the method of analyzing historical works and hermeneutics, this article aims to explore the thought of Mencius's kindness. Firstly, analyzing the background of thought. Secondly, illuminating the content of thought. It is hoped such an exploration can make people understand the keynote of the thought of Mencius's kindness. Finally, this article reveals to cultivates the kindness of students by education, and cultivates the sympathy of students for other people.