Roman, who usually hosts The Capital Breakfast Show on Monday to Friday, took to his Instagram after the exciting milestone - and fans couldn't get enough.
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Captioning a selfie with Alex, he penned: "Hosted @bbctheoneshow yesterday for the first time with the amazing @alexjonesthomson and loved it! Thanks for all the nice messages :) x."
Viewers couldn't wait to share their thoughts on the show and left messages for the presenter.
Roman shared the update with his 1.4 million followers
One fan penned: "So sick man. Congrats lad!!" A second wrote: "Awww just watched you on catch up you were brilliant loved it…"
A third replied: "You are amazing Roman." A fourth added: "Fab-u-lous loved it." A fifth said: "You're a natural!"
That wasn't the only show the 29-year-old turned his hand to recently, after he also appeared on Loose Men, a spin-off of Loose Women in aid of Mental Health Awareness Week.
Roman presented Loose Men last week
Roman was one of the panellists on the show on Thursday, alongside Vernon Kay, Mike Tindall and Johannes Radebe.
Fans adored the re-brand and even called for it to have a regular slot on ITV.
One fan penned: "Loose Men needs to be on one day a week, this show was brilliant today even my husband agreed as he sat and watched the whole show."
A second wrote: "Amazing advocates for men's mental health." A third replied: "Why is this not a regular programme? Such an important issue."
Roman is very close with his parents Martin and Shirlie Kemp
A fourth said: "Just watching it now, great show, well done chaps."
The star has been a huge advocate for men's mental health since the shock passing of his best friend and colleague Joe Lyons, last year.
Roman has continued to be outspoken about the important issue and even brought out a documentary with the BBC last March called "Roman Kemp: Our Silent Emergency"
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