The 25-year-old has scored six goals in 10 Premier League appearances for the Loftus Road club, who currently sit one place off the foot of the table.
Austin has been tipped for a call-up to Roy Hodgson's England squad in recent weeks and Redknapp believes the forward has the qualities to replicate the achievements of QPR legend Ferdinand.
"Charlie's played a handful of games now in the Premier League, but he's got to keep performing and scoring goals," he said. "We'd all love to see him in the England squad.
"I see a real spring in Charlie's step now he has scored against some top sides in the Premier League.
"If Charlie ends up being as good as Les Ferdinand, then we'll have one of the great strikers in English football."
Despite QPR's lowly league position, Redknapp is confident his side can make the necessary improvements to haul themselves out of trouble.
"We've had four good performances in a row now, which is good," he continued.
"It's taken a bit of time but I'm happy with the way we are playing and we keep improving."
Responding to the club's £20,000 fine over a misconduct charge for the reaction to a disallowed Austin goal against Manchester City a fortnight ago, Redknapp added: "I think that's a harsh fine.
"I don't think our players were overzealous in their appeals."
QPR visit Newcastle United in the Premier League on Saturday.
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