The announcement was made on the official Twitter page of the club on Friday, March 26.
Barreto had coached the Black Stars and Black Meteors in his previous stint in the country in 2003/2004, taking the latter team to its last Olympic appearance in Athens.
He left unceremoniously to handle Maritimo in his home country.
He has since coached in Russia, Saudi Arabia, Cyprus, Angola, Ethiopia and quite recently in Lithuania, handling FC Stumbras Kaunas.
Details of his deal with Asante Kotoko is yet to be known.
By Emmanuel Kwame Amoh|3news.com|Ghana