Hemiunu was a son of prince Nefermaat and a grandson of king Snofru of the 4th Dynasty.
There is no information about any wives of children of Hemiunu.
He was a vizier during the reign of his uncle, Kheops, and is credited for having been the architect of this king's pyramid at Giza.
Among his impressive titulary, there are several priestly titles as well. Thus we find that Hemiunu was priest for Bastet, Sekhmet, Mendes and Thot. It is possible that many of these priestly titles were purely honorific.
He is said to have lived until the 19th year of the reign of Kheops, which means that the Great Pyramid was either completed by then, or that it was completed by a different architect. He was buried in mastaba G 4000 at Giza, near the royal pyramid.
An impressive, life-size statue, 1.55m high, was found in a niche of his mastaba. It represents Hemiunu, seated on a block throne, his right hand decisively clenched, his left hand resting on his knee. His body is heavy, perhaps an indication that Hemiunu was rather fat, or perhaps just an indication that he was well-to-do. The statue's head has been restored, as it had been damaged around its eyes, which originally may have been inlaid with mountain crystals.
The statue is one of the many exhibits in the museum in Hildesheim, Germany.