The French photographer, who was once described by Diana as a “dream”, worked with many of Hollywood’s biggest stars.
The news was announced by his representatives on Instagram on Thursday.
“It is with great sadness that we announce the passing of Patrick Demarchelier on March 31st 2022, at the age of 78,” the post read.
“He is survived by his wife Mia, his three sons Gustaf, Arthur, Victor and three grandchildren.”
During his extensive career Demarchelier photographed a string of high profile celebrities including Beyonce, Jennifer Lopez, and Madonna.
He also produced the cover for the 1991 December issue front cover of Vogue, which featured Diana.
Demarchelier worked for a multitude of other top magazines including Harper’s Bazaar, Elle and Rolling Stone as well as many high-end fashion brands.
He helped shoot advertisement campaigns for Dior, Chanel, Yves Saint Laurent, Tommy Hilfiger and Carolina Herrera.
His prowess in the industry even earned him a mention in the 2006 Devil Wears Prada film, when he is sought after by fashion juggernaut Miranda Priestly, played by Meryl Streep.
Among those paying tribute to Demarchelier were US designer Vera Wang, and models including Bella Hadid, Cindy Crawford and Hailey Bieber.
Wang said she was “saddened to the core” by the news and would “always treasure” Demarchelier’s talent and kindness.
Sharing a picture of one of their final shoots together she wrote: “We began our fashion journey together on a SHOPHOUND shoot for American Vogue where he met his wife Mia.
“I will always treasure his talent, his kindness and our long history. So many sittings for Vogue, then ad campaigns for Vera Wang, the company.
“I am saddened to the core. To his wife and family, I send my love. May he rest in peace forever more.”
Celebrity hair stylist Sam McKnight, who also worked with Diana, said he had “so much” to thank Demarchelier for.
“Oh I am so sad to hear this,” he replied to the original post.
“I had the BEST TIMES with Patrick, endless incredible iconic photos, wonderful memories, a lifetime of laughter, I have so much to thank him for, there will never be another.
“Condolences to his beloved family.”
Posting on his own Instagram he added: “Oh, dear Patrick, how you made us laugh. Thank you for having me around for the beautiful ride. Rest in Peace my friend.”
Model Bella Hadid said: ”I am grateful to have been lucky enough to be in front of your lens.
“Most gentle , most legendary , soft but full of life . You will be missed Patrick. Rest In Peace. I will miss this day, and you dear Patrick.”
Sharing pictures of herself taken by Demarchelier, Crawford said “Rest In Peace, @patrickdemarchelier. Thanks for so many great memories and beautiful, timeless images.”
Actress Kate Hudson said she had “always enjoyed” working with the photographer and sent a “ton of love” to his family.
“So many memories. I had the pleasure of being photographed by Patrick often and always enjoyed him and his team so much,” she wrote.
“Sending a ton of love to his family.”