Johnnie Walker is taking a break from BBC Radio 2 for treatment for a heart condition.
The 73-year-old will step down from The Rock Show and Sound Of The 70s “for a number of weeks”, the station said.
Announcing the news on Twitter, his wife Tiggy promised fans he would be back at work soon.
“The good news [is] he’ll be even better when he returns with all that extra oxygen pumping round his body,” she wrote.
In a statement, BBC Radio 2 said: “On behalf of the audience and everyone in Wogan House, we wish Johnnie well and look forward to welcoming him back to the airwaves in the very near future.”
Walker was born in Birmingham and left school at the age of 15 to train as a mechanic. He later took a job as a car salesman.
In 1965, he quit his job to join pirate station Radio England and six months later joined the ship Caroline, continuing to broadcast in defiance of government legislation.
“I was a bit naughty, I disobeyed the law,” he said in 2006, as he collected his MBE at Buckingham Palace.
He started his BBC career on Radio 1 in 1969, and has been part of the Radio 2 line-up for the last 21 years, presenting the drivetime show from 1998 to 2006.
He took a nine-month break in 2003 to receive chemotherapy for a form of non-Hodgkins lymphoma. On his return, he thanked his wife “without whom I don’t think I’d have made it through”.
The nature of his heart condition has not been disclosed, but Tiggy Walker said the DJ expected to be back on the air within “six weeks”.
Huey Morgan will present The Rock Show and Tom Robinson will host Sounds of the 70s in his absence.