Principal jobs of a Toshi choja were to establish the political base of his clan, to manage the shoen (manor in medieval Japan) in the territories of the clan and movable properties, to manage Kofuku-ji Temple, the family temple of the clan, and to manage Kasuga-taisha Shrine and Oharano-jinja Shrine, both shrines of the clan.
藤氏長者の職掌を大きく分けると、政治的な藤原氏の存立基盤整備、氏領としての荘園や動産の管理、氏寺興福寺や氏社春日大社・大原野神社などの管理があげられる。