The television icon and father of former Strictly dancer Zoe Ball will become the oldest contestant on the regular BBC One show if he takes part.
The 74-year-old is said to have impressed producers after taking part in training sessions, reports The Sun.
A BBC source said: "Johnny might be 74, but he's got some puff. He has looked after himself over the years and is really game. It would be foolish to write him off as some old duffer just there for laughs, like John Sergeant.
"He's been showing off some moves in training that would put much younger celebs to shame."
Zoe Ball would also be in line to interview her famous father on spin-off show It Takes Two.
Johnny Ball was one of the biggest TV hosts of the 1970s and 1980s, and appeared on the likes of Play School, Think of a Number and Johnny Ball Reveals All.
June Brown is the oldest contestant to have competed on a Strictly Come Dancing Christmas special, taking part in December 2010 at the age of 83.
The latest Strictly Come Dancing series will launch on Saturday, September 15 on BBC One.
Girls Aloud singer Kimberley Walsh is said to have signed up for the show, while other names have included Jerry Hall, Fern Britton and former England cricket captain Michael Vaughan.
In pictures - rumoured Strictly celebrities:
Copyright: PA Images Dominic Lipinski/PA Wire