No cause of death was given Friday for the man credited with defining Jacqueline Kennedy's style, The Los Angeles Times reported Saturday.
Cassini was not only an innovative leader in the fashion industry, he was a major Hollywood player as well, married to actress Gene Tierney, engaged to Grace Kelly before she became princess of Monaco and a regular on TV talk shows as "The Tonight Show and "The Mike Douglas Show."
He was the first fashion designer to franchise and had as many as 50 licenses for items such as sunglasses, watches and children's clothes, The Times said. At one point, Cassini's estimated worldwide retail volume was estimated at $400 million.
After becoming the fourth ex-husband of cough syrup heiress Merry Fahrney, Cassini moved from New York to Los Angeles in 1940, where he worked for major studios designing costumes for Veronica Lake, Marilyn Monroe and Tierney, whom he married in 1941.
Tierney was exposed to rubella by a fan while pregnant with their daughter, Daria, who was born blind and severely retarded.
They divorced in 1947, then reconciled and had a second daughter, Christina, but divorced again in 1952 and remained friends until Tierney died in 1991.
In later years, Cassini became an animal activist and introduced micro-fiber fake furs in 1999.
He is survived by his daughters and grandchildren.