Looting of the country's cultural heritage has increased since the popular uprising that ousted Hosni Mubarak in 2011 and during the years of political turmoil that followed.
The huge National Museum of Egyptian Civilisation was created in collaboration with UNESCO and has yet to open to the public.
"Two curators were arrested while replacing a pharaonic statue of (fourth dynasty) King Menkaure, discovered in Luxor's Karnak temple, and an ancient Islamic lantern with fake ones," Antiquities Minister Mamdouh al-Damati said in a statement.
A ministry committee will make an inventory of the "priceless" collection that includes artifacts from prehistoric times to the present day, the statement added.
