The Blues are currently sitting at the summit of the table with 22 points – but Manchester United are just four behind them in second.
And Di Matteo is aware of the game's significance, describing it as a "classic" and declaring his intention to capitalise on United's recent defensive complications.
"It's a massive game for both clubs and a classic in the fixture list," Di Matteo told reporters.
"They are conceding a few goals and we have a big threat as well with our players, so we will try to exploit those weaknesses.
|CHELSEA V MAN UTD PREVIEW
|10/1||Oscar is 10/1 with bet365 to open the scoring against Man Utd on Sunday
"We know Man United very well and they are always very difficult games. But we have to take advantage of our home crowd and our home pitch and play with the belief and confidence we've shown so far."
Di Matteo is also keen for Chelsea to put their 2-1 defeat to Shakhtar Donetsk behind them, citing the United clash as the perfect opportunity to do so.
He continued: "After a defeat, it's not the best within our dressing room, but we have a great game coming up on Sunday and I think we can prove to everybody that we are a strong team.
"They've recovered from a defeat in the first game very well. They are a strong team and were at the top last season and you wouldn't expect them to be anywhere else."
However, one thing the Italian manager insisted he would not engage in is the practice of mind games.
Manchester United boss Sir Alex Ferguson has been notorious over the years for his use of the media, but Di Matteo doesn't think he himself needs to take such an approach.
Di Matteo added: "If I need to, I will, but there is no need and sometimes it doesn't have to be publicly.
"They didn't work last season, I think. You make it out a little bit more than it is at the end of the day.
"As a manager, you have to prepare your team as good as you can and then the players have to go on the pitch and perform."