In a statement on Friday (18 November), Global Radio said that after nearly eight years, both Global and Vaughan had agreed that "now is the right time to step down".
Former ‘Big Breakfast’ presenter Vaughan replaced Chris Tarrant as host of the Capital Radio breakfast show in April 2004 and his contract was renewed by then owner GCap Media for a further three years in 2007.
Vaughan and his co-host Lisa Snowdon are currently the number one commercial radio station hosts at breakfast time, with an average weekly reach of 1.13 million in the third quarter of 2011, according to Rajar.
Vaughan said: "I have just loved doing this job, but after all these years of getting up in the middle of the night, I really think the time is right to hand over the microphone to someone else.
"It's been a joy waking up London every morning and a thrill to have been part of the broadcasting tapestry of this great city."
Snowdon will continue on the show. She will be joined by Greg Burns from today (21 November) but a spokesman for Global Radio said a replacement announced would be announced in due course.
Richard Park, director of broadcasting, Global Radio, said: "Johnny has done a fantastic job over the years, particularly recently, building the programme with Lisa Snowdon, into London's most popular commercial radio breakfast show.
"Johnny is a skilled broadcaster on radio and television, and we thank him for his time with 95.8 Capital FM, while wishing him every success for the future."
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