The now Internazionale defender left Goodison Park in the summer of 1999, following a disappointing season in England.
At the time of the transfer, Everton inserted a sell-on clause and they say they have yet to receive any money from Perugia.
Inter signed Materazzi 15 months ago, and Everton are claiming they are due £500,000 from Perugia.
Goodison officials contacted the Italian FA and Fifa, but have yet to receive anything from the Serie A side.
The Toffees say they have been forced into starting legal proceedings by Perugia`s apparent reluctance to meet their debt.
Everton's Head of Corporate Affairs and PR, Ian Ross told the club`s website: "As a club we have shown patience and understanding but we now have no alternative but to move this matter into the legal arena."
