The singer - who was previously wed to Radh Ramen for one year and Uri Frutmann for 12 - tied the knot with Dr Mitch Besser in front of 150 close friends and family in London on Saturday (15.09.12), with her two daughters from her second marriage, Tali and Lola, acting as bridesmaids.
Annie`s spokeswoman released a statement saying: "On Saturday 15th September 2012, AnnieLennox and Dr Mitch Besser were married in a private ceremony with friends and family present."
A source who attended the nuptials told MailOnline: "It was just a really relaxed, friendly occasion. Everyone seemed happy, especially Annie who was beaming."
Guests, including Colin Firth and Ruby Wax, helped the couple to celebrate at a boat party on the River Thames, with Annie taking to twitter to share her joy.
Posting a picture of her bouquet, she wrote: "Wedding flowers: 15 September 2012."
Annie met the doctor in 2009 after becoming involved with his charity Mothers2Mothers which helps children and single mothers with AIDS.
However, he was married at the time and the couple are believed to have only started dating after he and his wife Debra Jackson - with whom he has two teenage sons - started having difficulties before she filed for divorce last year.