Sale have been talking to de Marchi since the New Year and di Marchi has penned a two-year contract to move to Manchester from Italian side Treviso, who play in the Rabo Direct Pro 12.
And Sale director of rugby Steve Diamond admitted he was elated at de Marchi's capture.
"Alberto's a very good player and we are absolutely delighted to have signed him," said Diamond.
"He's a good age, being just 25, and he's also versatile in that he can play both sides of the scrum at tight head and loose head, though we see him as a tight head in the main.
"And I think Alberto will fit in very well with our other props Vadim Cobilas, Ross Harrison and Fridge (Eifion Lewis-Roberts).
"Alberto is a good scrummager, he is very mobile around the pitch, he's also a good defender and we're very happy to have him on board.
"Alberto has just had a very good Six Nations with Italy.
"And I've no doubt he'll prove to be a really big asset for us over the next few years.
"A lot of work and due diligence has gone into signing Alberto.
"We've watched him both with Italy and before in his club games with Treviso..
"Toulon tried to sign him but fortunately, we've been able to bring Alberto here."