The statement released by the couple last night read: "Lenny Henry and Dawn French are sad to announce they have decided to separate after 25 years of marriage.
"They made the decision last October and since then have been living together in constant, open and honest discussion.
"The separation is entirely amicable and they fully intend to maintain their close friendship.
Henry, 51, and French, 52, married in 1984 and have an 18-year-old daughter called Billie.
As well as being veterans of stand-up comedy and sketch shows, both have appeared on stage and screen as actors.
After making his name as a funnyman, Henry – originally from Dudley in the West Midlands – turned his hand to Shakespeare, winning critical acclaim and an award for best newcomer for his portrayal of Othello last year.
French, a familiar face as one half of comedy duo French and Saunders, played the lead role in hit TV series The Vicar Of Dibley, which ran from 1994 to 2007.