The tomb of Betah Mes, who was also a royal scribe and in charge of the state granaries, dates back to the 19th dynasty, which ruled Egypt between 1320 and 1200 BC.
Antiquities chief Zahi Hawass told AFP that the 70-metre-long (yard) tomb, discovered in the Saqarra necropolis, south of Cairo, branched off into passages and prayer rooms.
Workers unearthed reliefs depicting offerings to deities and the deceased and his family worshipping a trinity of gods, Amun, his wife Mut and their son Khonsu, said Ola el-Ugaizi, who headed the expedition.
The tomb also contains reliefs of Mes and his family hunting and fishing in the Nile river, and Ushtabi figurines which ancient Egyptians believed would serve the deceased in the afterlife.
But the expedition's spokeswoman Heba Mostapha said the tomb had been looted and its pillars used to build churches.
"Part of the destruction we found in the grave was because its pillars were used to build churches in the Christian period and it was looted in the 19th century in the period of Mohammed Ali Pasha," she said.
The team was continuing its search for the tomb's main chamber, where they believed they would find Mes's mummy and perhaps that of his wife.