The former newspaper editor proposed to journalist Celia Walden during a holiday in France last week (beg07Dec09) while they were celebrating her birthday.
The TV star, who has been dating Waldon since 2006, revealed the happy news in a post on his official website.
The statement reads, "Piers has taken the plunge and proposed to his girlfriend of four years Celia Walden - and she said yes!
"The happy event took place last week in that most romantic of cities - Paris, where the couple were celebrating Celia's birthday."
Morgan divorced Marion Shalloe in 2008, they have three sons together.