Environment minister Ben Bradshaw is to become the first MP to hold a civil partnership ceremony.
Mr Bradshaw will have a party for family and friends
The 45-year-old Labour MP for Exeter is to "tie the knot" with BBC Newsnight journalist Neal Dalgleish in June.
Mr Bradshaw had indicated his intention to have a ceremony before same-sex civil partnerships passed into law in England and Wales last December.
A spokesman said there would be a party for family and friends at Mr Bradshaw's sister's home in Herefordshire.
The MP, first elected to Westminster in 1997, was previously a BBC correspondent, covering events such as the fall of the Berlin Wall.
There were 3,648 civil partnership ceremonies between 21 December and 31 January last year, according to Office for National Statistics figures released last month.
Mr Bradshaw's spokesman said: "Ben Bradshaw and his long-term partner, Neal Dalgleish, are to register their civil partnership in June this year.
"To celebrate the occasion they're giving a party for family and close friends at Ben's sister's home in Herefordshire."
Former Cabinet minister Chris Smith was the first MP to declare his homosexuality but Mr Bradshaw is thought to be the first to have done so before being elected.
The news of the civil ceremony has been welcomed by Labour supporters in Exeter.
Councillor Roy Slack said: "We congratulate him and want to wish Ben and his partner all the best for the future."