Mexico's National Institute of Anthropology and History (INAH) said a further 119 skulls had been uncovered.
The tower was discovered in 2015 during the restoration of a building in the Mexican capital.
A similar structure to the Huey Tzompantli struck fear in the soldiers accompanying the Spanish conqueror when they invaded the city. The cylindrical structure is near the huge Metropolitan Cathedral built over the Templo Mayor, one of the main temples of Tenochtitlan, now modern day Mexico City.