Don Diego Tlilpotonqui was the tlatoani ('ruler' or 'king') of the pre-Columbian Acolhua altepetl (ethnic state) of Tepetlaoztoc in the Valley of Mexico.
Tlilpotonqui was the grandson of Cocopin, who had previously been ruler of Tepetlaoztoc.
Upon Cocopin's death, his wife Azcasuch, a daughter of Nezahualcoyotl, the ruler of Texcoco, succeeded him as cihuatlatoani (queen regnant).
With his conversion to Christianity, Tlilpotonqui was baptized and given the Spanish name Diego.
Upon his death, his nephew Don Luis de Tejada became tlatoani.