The 33-year-old Chelsea midfielder started on the bench against Bulgaria on Friday, sparking speculation his international future could be coming to an end.
It was the first occasion Lampard had been left out of an England starting line-up, when fit and available, for a competitive game since the Euro 2008 qualifying campaign.
He could return for Tuesday night's Euro 2012 clash with Wales at Wembley.
"Frank Lampard is a really important player," Capello said at a press conference televised by Sky Sports News, "like others that are here and some players that are not here like (Jack) Wilshere, Steven Gerrard and other ones.
"I think he's ready to play with us.
"I don't know if he will play.
"Probably we can change the style to a different style to the one we played against Bulgaria because we are playing at home."
Highlighting Lampard's importance to the England cause, Capello said: "He is one of the important players and one of the leaders of this squad."
Capello stressed England will need to be at their best to overcome Wales, having been impressed by Gary Speed's side beating Montenegro on Friday.
"It's very important to win and beat Wales," Capello said.
"Wales are in really good form.
"It will be a really, really dangerous game."
The Italian played down concerns about striker Andy Carroll's fitness, which he raised after the Bulgaria game.
He said: "Andy trained really well. I'm really happy with how he started in training and he needs to do the same when he goes back to Liverpool.
"I think he will be a really important player for Liverpool and us."
England captain John Terry, meanwhile, believes his Chelsea team-mate Lampard should not be written off despite falling to the bench in Friday's match in Bulgaria.
"Write Frank Lampard off at your peril," he said.
"I have known him an awful long time and he was disappointed about not starting but trained incredibly hard the day after and he remains one of the best players I have ever played with.
"Because of his age people tend to right him off but he is still in excellent form. His record for England has been incredible."
Terry revealed all of England's established names are aware that there are a number of players now vying for a starting role in the set-up.
He said: "I think we all feel that in the squad, that has come in conjunction with the younger players really pushing on and playing well for their club sides.
"People said we maybe took it for granted, playing in the side but that has never been the case since I have been involved for England.
"It is a great mixture in the squad and I think Frank will rise to the occasion and will be back in the side very soon.
"We saw the other night Chris Smalling did well and Gary Cahill alongside me. Its not just Frank, we all feel pressure from the younger players for our places."
England face Wales having not won in their previous four games at Wembley, but that is something that does not worry Terry.
"People can look too much into that," he said.
"I have gone long spells at home without winning, it chops and changes and its just one of those things we are going through. It would be nice to change that sooner rather than later."
The fixture follows Wales' first win of the qualifying campaign - a 2-1 victory over Montenegro - and Terry reckons there will be no repeat showing of the one-sided win they had over the Welsh in Cardiff back in March.
"I think it will be very different from the last game," he said.
"We got off to a good start then but we are expecting a tough game and they will be full of confidence after their win.
"Everyone (the players) will probably know each other inside out, ideally it would be nice to get off to a good start like we did in Bulgaria but that doesn't always happen but it is important the fans stay with us."