The Italian lawyer has claimed that the former England manager, who released his memoirs last week, has breached a confidentiality agreement with some of the contents written in the book.
"I just started legal action against the publishers," Dell'Olio told yesterday's This Morning show.
"He is in breach of confidential order that we cannot talk about certain details, so I am surprised at the publishers. It's breach of confidentiality."
Eriksson, who wrote the book with Headline, had two affairs during his nine-year relationship with Dell'Olio.