The purpose of this study is to examine the connotation, classification and function of self-modesty com-prehensively from cultural and historical perspective. In Study 1, through the retrieval of ancient Chinese books, 889 articles describing self-modesty had been collected, with 109 (12%) of them on its connotative, 112 (13%) on classification and 616 (69%) on function. The content analysis of these ancient books showed that self-modesty, divided into “real” and “false”, referred to an attitude or behavior with which one hid or evaded his or her own advantage or success. Its functions included harmoniousness, aggressiveness, defensiveness, courtesy, and morality, accounting for 4.7%, 4.1%, 40%, 5.3%, and 12%, respectively, of the ancient books. In Study 2, the open investigation was carried out among 217 university students and the general public. The results showed that modern people held almost the same views as those in ancient times on the connotation of self-modesty, as 84% believed that self-modesty was still of a considerable realistic significance. However, they differed in terms of the identity content and emphasis of self-modesty’s function, which could be caused by the differences in expressions, the nature of language materials, and the manoeuvrability of classification. In Study 3, a self-prepared survey was conducted on identity commitment among 486 university students. The results indicated that university students laid enormous emphasis on the functions of self-modesty including defensiveness, ego integrity, and image promotion. Different from the concepts of “negative illusion” and “below-average effect” in western theories, self- modesty is the embodiment of Chinese dialectical thinking and their pursuit of society-oriented self- actualiza-tion. Its functions can be summed up in two macro dimensions–“instrumental” and “transcendence”. Therefore, more priority in future studies should be given to the contextual situation and socialization of self- modesty.