The 57-year-old, who Diana famously described as her “rock”, will tie the knot with Graham Cooper, 58, in April.
Paul divorced his wife Maria six months ago, after 32 year of marriage.
His spokesman confirmed his happy news, saying: “I can confirm their forthcoming marriage.”
His family and friends are said to be delighted that the couple have decided to make it official.
The couple are are going all out for their big day with a circus-themed ceremony at a five-star venue in the Lake District.
Following Diana’s death in 1997, Paul wrote several books about his time working in the Royal household.
In 2004 he took part in ‘I’m A Celebrity… Get Me Out Of Here!’. He’s also been rumoured to be taking to the ‘Strictly Come Dancing’ dancefloor on a number of occasions.
He recently opened up to his ex-wife Maria and their grown up sons Alexander and Nicholas about his decision to wed Graham.
In a joint statement released last year the Burrells confirmed they were divorcing.
It said: “Our clients Paul and Maria Burrell would like to end any speculation over the past few days by confirming that they are currently going through a divorce.
“The decision to file for divorce was a mutual one, both Paul and Maria remain the best of friends and have two wonderful sons who remain their priority.
“Paul and Maria will not be giving any further comments and would request that their privacy is respected during this time.”