"He will be greatly missed", the company said.
Hubert de Givenchy has died at age 91. He maintained low overhead costs to keep down the prices of his designs.
The designer, who stood at a towering 1.98m (6ft 6in), won instant acclaim for his first collection at the age of 24. He also inspired the the initial concept for "the little black dress", after designing Hepburn's in Breakfast at Tiffany's. "You must never upset it, if you want the material to speak", he said. "He is far more than a couturier; he is a creator of personality". He designed her wardrobe for seven films, as well as looks for her off-camera life - including an above-the-knee pale pink dress worn on the day of her wedding to Andrea Dotti. He is also known for outfitting American Royalty, First Lady Jacqueline Kennedy. "It was...an enormous help to know that I looked the part", began Hepburn, some time ago.
He continued: "We did all the fittings in secret. She gives me direction".
Grace Kelly and Jackie Kennedy were other famous clients of Givenchy, a name synonymous with understated elegance. Givenchy's legacy spans more than 60 years and it is still relevant today as it was in the 1950s. He sold the brand to LVMH Moet Hennessy Louis Vuitton in 1988 and has been succeeded there by designers including Alexander McQueen and Riccardo Tisci, who was named artistic director of Burberry March 1.
Bernard Arnault, CEO of LVMH, said he is "deeply saddened" by Givenchy's death.More news: Nepal plane crash: death toll rises to 40
Hubert de Givenchy in 2002.
Known for his ideal manners and old-school charm, the tall and incredibly handsome designer was considered to be the pinnacle French elegance and refinement. "I extend my most honest condolences to his family and to all those who have known him".
His partner Philippe Venet, a former haute couture designer, confirmed the news to the AFP news agency.
"He revolutionised global fashion with the timelessly stylish looks he created for Audrey Hepburn, his great friend and muse for over 40 years", the house of Givenchy said in a statement on Monday.
Nina García, Elle magazine's editor-in-chief, posted: "RIP Hubert de Givenchy".
He liked to call himself the "eternal apprentice", forever seeking new inspiration and ideas. He believed in beauty and he left us a more lovely world. The fashion world celebrated Givenchy's first collection, giving him credibility among Parisian couturiers and, soon after, Hollywood. "I hope you can now reunite with your teacher Balenciaga".