[Purpose/significance] By attributing the common phenomenon that the number of female librarians is more than that of male librarians to gender culture, this paper aims to interpret the social roles of librarians from the multiple perspectives.[Method/process] With the help of the basic concepts and views of gender theory, this paper analyses the sex ratio imbalance of librarians from perspectives of sex division of labor, gender stratification, gender relationship and gender stereotypes.[Result/conclusion] As long as the traditional gender culture is the mainstream ideology of the society, the phenomenon of the sex ratio imbalance of librarians will inevitably occur, which is decided by its essence of cultural construction and the value judgment of librarians' profession made by society.