"He [Terry] hasn't got the armband but he's still a great player and a great leader," said Rooney.
Rooney also said he was fit for the Wembley fixture despite suffering discomfort in his knee on Sunday.
Wednesday's match is England's first since allegations were made that Chelsea captain Terry had an affair with the ex-girlfriend of Wayne Bridge - a former team-mate at Stamford Bridge and with England - who now plays for Manchester City.
Rooney expects to recover from his knee injury and face EgyptTerry, 29, was taunted by City fans during his team's 4-2 home defeat on Saturday, when Bridge refused to shake his hand before the kick-off.
Bridge said last week he no longer wished to play for England because his position in the squad had become "untenable and potentially divisive"
However, Rooney said he expected Terry to get "the same as normal" reception at Wembley on Wednesday.
"The squad has been no different since we met up," said the striker, who came off the bench to score Manchester United's winner in their 2-1 Carling Cup final victory over Aston Villa at Wembley on Sunday.
"I've been in the team when a few players have been booed at Wembley and it's not nice - it doesn't send the right message.
"I hope he gets a good reception. When you are leading up to a World Cup, you want the fans behind us and giving us their full support because that will be really important."
Fears of a hostile reception for Terry follow England fans' boos aimed at his Chelsea team-mate Frank Lampard during England's Euro 2008 qualifying win against Estonia in 2007.
After all the optimism of a decent World Cup run this year, it's looking a bit shaky h2k8 Lampard's then team-mate Joe Cole slammed the fans at the time, saying: "Frank has been one of England's most consistent players over the years and he has never let England down.
"It is not nice to hear that, it is not nice to hear one of your mates getting that. He doesn't deserve it."
Rooney, who has scored 28 goals in all competitions for Manchester United this season, added: "Wayne Bridge is a fantastic player and especially now with Ashley Cole being injured I'm sure he'd have been the one to take his place. It's unfortunate but it's his decision and you have to respect it."
The striker suffered a knee problem during Sunday's final but said: "It's OK. I went for a scan and it's just a bit of bruising. I'll be fit to play."
He added that there had been no disruptions in the run-up to England's final game before manager Fabio Capello's provisional World Cup squad is announced, despite the unusual circumstances surrounding preparations.
Meanwhile, Villa's James Milner said he is prepared to play at left-back, should Capello want him to fill the problem position.
"To have Wayne Bridge available would be great but we'll move on," said Milner.
"I've had 15 minutes experience at left-back but that was for England. If I'm asked to play there I'll do the best job I can - but my best position is further forward, in central midfield or out wide."
I hope John gets a good reception. When you are leading up to a World Cup, you want the fans behind us and giving us their full support because that will be really important Wayne Rooney And both Rooney and Milner said Stoke defender Ryan Shawcross, who is in an England squad for the first time and whose challenge on Aaron Ramsey at the weekend resulted in a double compound fracture for the Arsenal midfielder, had been made welcome.
"I was with him at United for a couple of years and he's not that type of player," said Rooney. "I'm sure he'll be OK, he'll be welcomed into the squad and will be hoping to get a game on Wednesday.
"It's unfortunate but he's got to move on now. He's in the squad at a young age, it's important for him to get a game and if he does I'm sure he'll do well."
Milner said: "He'll come to terms with it. Hopefully this will give him some confidence, help get his mind back on football."
Rooney had earlier revealed he knew last Wednesday that he would not start the Carling Cup final but said it was not because of the knee problem.
"I had a little bit of a stomach bug and the manager was looking for an excuse to leave me out," the forward said.
"When he found out about that it made his mind up. I was still disappointed but it was the correct decision by the manager."
Rooney's Manchester United team-mate Rio Ferdinand did not join the England camp in Watford.
Instead, he will have further treatment on his back injury in the hope of being fit for Manchester United's Premier League trip to Wolves on Saturday.