Lampard's international career was thrown into question on Friday after Capello dropped the 33-year-old from the starting line-up against Bulgaria - the first time in nearly four years the midfielder had been left out.
It followed Lampard's substitution at half-time in June's UEFA EURO 2012 qualifier against Switzerland and prompted many to speculate that the Chelsea veteran's England career may be drawing to a close.
However, Capello insisted Lampard remained part of his plans as England prepared for tomorrow's Group G game against Wales at Wembley.
"Frank Lampard is a really important player like others that are here and some players that are not here like [Jack] Wilshere, Steven Gerrard and other ones," Capello told a press conference. "I think he's ready to play with us. I don't know if tomorrow he will play.
"Probably we can change the style to a different style to the one we played against Bulgaria because tomorrow we are playing at home. He is one of the important players and one of the leaders of this squad."
"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 write him off but he is still in excellent form. His record for England has been incredible."
No concern over Carroll
Capello, meanwhile, warned England against complacency as they prepared to face a Welsh side who have been rejuvenated by a 2-1 victory over Montenegro last week. "It's very important to win tomorrow and beat Wales," Capello said. "Wales are in really good form. It will be a really, really dangerous game tomorrow."
He also played down concerns about Andy Carroll's fitness after the £35million Liverpool striker failed to make the bench for last week's win over Bulgaria in Sofia.
"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," said the Italian. "I think he will be a really important player for Liverpool and us."