The 25-year-old defender has agreed an 18-month deal with the Glovers after turning down a new deal with the Latics, managed by Lee Johnson, son of Yeovil boss Gary.
In his spell with the Latics Matteo made 15 appearances and scored two goals before leaving the League One club last week.
"I have seen him a few times when I have watched Oldham this season, and I was impressed by him," Johnson told the club's official website.
"He is a typical Italian defender who can play anywhere across the back four, and he's introduced himself to the lads this morning (Thursday) in training by knocking a few about; he's competitive.
"In January it's hard to sign players as opposed to loans, but we are delighted to have signed Matteo on a permanent deal."
Lanzoni added: "I am delighted to sign for Yeovil Town. It is a great opportunity for me to play Championship football and I am looking forward to the challenge ahead."
- Sports & Recreation
- Lee Johnson