Rabbi David HaNagid was born in Cairo on 24 Tevet 4983 (1222). He was the son of Rabbi Avraham, son of the Rambam. It was long thought that he was born in 1212, but a Cairo Genizah document concerning his birth established the date as 1222. He was fifteen when his father passed away.

Appointed around 1245 as Nagid, head of the Jewish communities of Egypt, Syria and the Land of Israel, he served his first years under the protection and guidance of his maternal grandfather, Rabbi Chananel ben Shmuel. In 1250 his appointment was challenged and he had to flee with his grandfather to Jerusalem or Alexandria; he regained his office in 1252.

In 1285 he was deposed once more and moved to Acre. While there, he led the struggle against the movement opposing the Rambam's writings, headed by Rabbi Shlomo Petit and other sages. In 1291 he returned to Egypt and resumed his position as Nagid, which he held until his death.

Tradition attributes three works to him. Works: Midrash David, sermons on Genesis and Exodus in Arabic, which were read in the synagogues of the East on Shabbat after Mincha; Midrash David on Pirkei Avot, also in Arabic, read on the Shabbatot between Pesach and Shavuot; and a never-printed commentary on the "prophecy of the child," a text on the End of Days. The scholar Paul Fenton, however, believes the Midrash David was written by a later author.

His son, Rabbi Avraham HaNagid, was the father of Rabbi Yehoshua HaNagid. Rabbi David passed away in Egypt on 1 Elul 5060 (1300). According to tradition he was brought for burial to Tiberias, near the tomb of his grandfather the Rambam; a tombstone bearing his name, found in the 20th century and kept in Cairo, has been shown to be a late forgery.