The artefact is inscribed with complete cuneiform text - a system of writing on clay in an ancient Babylonian alphabet.
Italian authorities handed it over to Iraq's President Abdul Latif Rashid in the city of Bologna last week.
It is not clear how the tablet was found - or how it made its way to Italy where it was seized by police in the 1980s.
Iraqi Culture Minister Ahmed Badrani said that it might have been found during archaeological excavations of the Mosul dam, which was built around that time.
Iraq, often described as the "cradle of civilisation", is known, among others, for the world's first writing.
In the late 8th Century, the country's Bayt al-Hikmah [House of Wisdom ] was home to the largest library of books on science, art, maths, medicine and philosophy.
Looting of the country's antiquities intensified following the US-led invasion 20 years ago.
Iraq's president praised the co-operation shown by Italy and said he would work to recover all the archaeological pieces of Iraqi history from abroad.