The couple have been seen at several celebrity events
Ulrika Jonsson is set tie the knot with her boyfriend Lance Gerrard-Wright, the man who offered himself as the prize on a TV dating show she presented.
The couple, both aged 35, met during the filming of the ITV1 show Mr Right, in which 15 women competed for the chance to date the eligible bachelor.
Jonsson fronted the show from the house where the 15 women lived together, but it was a ratings disappointment and was moved to an 11pm time slot.
Mr Wright failed to find romance through the programme and proposed on Thursday, having been seen out recently with the TV presenter at celebrity events.
Jonsson told the News of the World the proposal, on the steps of St Paul's Cathedral in London, was "incredibly romantic" and she did not hesitate to say yes.
"He chose St Paul's because it's one of his favourite churches. We're so in love and I'm so, so happy," she told the newspaper.
The Swedish presenter has previously been linked with England football coach Sven-Goran Eriksson, soccer star Stan Collymore and James Crossley - alias Hunter from the TV show Gladiator.
She has two children - baby Bo, by former partner Markus Kempen, and eight-year-old Cameron, son of ex-husband cameraman John Turnbull.