Mariah Carey flew in from the US to perform at the star-studded reception in London.
David and Iman met in 1990 with the singer saying he "just knew she was the one."
Iman has shared a moving tribute to her late husband David Bowie on what would have been their 24th anniversary.
The supermodel posted a black and white picture of the couple on her Instagram account with the caption 'June 6th... 24th wedding anniversary #foreverlove'.
Written across the picture are the words 'The best thing about me is you' and the photo which shows the pair very much loved up, comes from a shoot with HELLO! magazine.
Iman has been keeping a low profile since the passing of her husband and she also lost her mother just two months after David's death.
“You have to be at the right time in your life that you’re ready for an everlasting relationship, that it becomes first, a priority in life. If your career is important to you, don’t get married and have children, because something will give.”