The outer decontamination bag from the Apollo 11 mission in 1969 was bought at Sotheby's by an anonymous bidder.
The white bag still carries traces of Moon dust and small rocks.
The auction comes after a legal battle over the ownership of the only artefact from the Apollo 11 mission which was in private hands.
After the spacecraft returned to Earth, nearly all the equipment was sent to the Smithsonian museums.
However, the bag was left in a box at the Johnson Space Center because of an inventory error.
It was then misidentified during a government auction, selling for just $995 to a lawyer from Illinois in 2015.
Nasa later tried to get the bag back, but earlier this year a federal judge ruled that it legally belonged to the buyer, who then offered it for sale at Sotheby's.