Materazzi described life under Benitez at Inter as like "being back at school", suggested the Spaniard had been lined-up as Jose Mourinho's successor while the Portuguese was in position and had told him to take down photographs in his locker of his former coaches.
"He's lying," Benitez said.
" Marco Materazzi is lying. He's lying, just lying. Everything that he said is a lie. Simple.
"When he was talking with Mourinho it's a lie, because nobody knew I was going to Inter, even me. It's a lie.
"About the pictures, it's a lie. So he's a liar."
Benitez refused to discuss off-field events at Chelsea, including contract discussions for senior players like John Terry, who is in line for a return to the starting XI in the Capital One League Cup semi-final second leg at Swansea, where the Blues must overturn a 2-0 first-leg deficit.
Benitez refused to comment on reports of Real Madrid boss Mourinho, who was popular and hugely successful during his spell at Stamford Bridge, being in regular contact with Chelsea owner Roman Abramovic and players in west London.
"We talk about contracts and other things at the other window. This window is for football and tactics."
Benitez confirmed England left-back Ashley Cole has agreed a one-year contract extension at Chelsea, with the details still to be finalised on the deal which keeps him at the club beyond the end of the season.
Benitez said: "Everything's agreed and the club will announce when everything is done."
Midfielder Frank Lampard's time appears likely to end this summer, Benitez pointed to the non-football window when asked about Terry, whose current deal has 18 months remaining.
Terry has not started since November 11 when he suffered a knee injury in the first half of the draw with Liverpool.
Asked if Terry has been frustrated by his lack of match action since returning to contention, Benitez added: "No. I think he knows he will need time.
"We have a plan with him and we're working, following the plan.
"He's training well. He will need match fitness. He'll be involved in the squad and is an option."
He said: "It's not easy for us to play both at the same time given the quality of the players playing behind. It's an option for 15 minutes, and we can do it if necessary.
"We have confidence that we can do it. It's not easy, but we've done it before in other stadiums and we can do it.
"We have to score and win. For them, it depends: 2-0 up, they could wait and play counter-attack.
"They could try to pass the ball and attack, but I think they will wait for us.
"We have to go there and try to win. Not just 1-0 - we have to do a bit better than that. But we can do it. We have enough quality."
The Capital One Cup is an important competition for Chelsea after Benitez recently made it clear he believed they were out of the Barclays Premier League title race.
Defender Gary Cahill contradicted his manager, saying following Sunday's win over Arsenal which saw his side move 11 points behind leaders Manchester United, that Chelsea are not out of contention for a domestic treble.
"He ( Cahill) has confidence in the team," Benitez added.
"He knows we can win. If we want to win three trophies, we'll have to win this game."
With speculation linking Pep Guardiola to Chelsea at an end following his agreement to coach Bayern Munich, a trophy would strengthen Benitez's claims for a permanent contract.
The former Liverpool boss again gestured to the other window.
"I'm really pleased to be here, to have a great job in a top side, and I'll try to do my best until the end," he said.
"I'd like to win trophies and to have the opportunity to challenge for trophies."