The British TV, film and stage actor passed away after a long illness, his agent confirmed.
He was perhaps best known for roles such as Bishop Gardiner in The Tudors, Sir Monty in Judge John Deed and the Duke of Buckingham in The Three Musketeers.
His agent released a statement saying that he passed away peacefully with his wife Alexandra and daughters at his bedside.
Ward studied at the Royal Academy of Dramatic Art (RADA), while becoming a stage actor in Northampton, Birmingham, Oxford and London.
His first big TV role saw him play Winston Churchill in Richard Attenborough's film Young Winston in 1972 opposite Anthony Hopkins and Anne Bancroft.
In 1973, he played the Duke of Buckingham in The Three Musketeers, a role he reprised in its sequel a year later.
He was cast as author James Herriot in the original film adaptation of All Creatures Great and Small in 1974.
Ward appeared in many TV dramas, including Lovejoy and Ruth Rendell Mysteries, and in recent years became a series regular in Judge John Deed and in Showtime's The Tudors until 2010.
He had returned to the stage in recent years, including tours of Alan Bennett's The Madness of George III and Oscar Wilde's An Ideal Husband.
The actor was also the victim of a street attack in the late 1980s that remains unsolved.
He also famously stepped in at the last minute to replace Stephen Fry in the West End play Cell Mates after Fry walked out of the production.
Simon Ward's daughter is the actress Sophie Ward, while his youngest daughter Kitty is married to comedian Michael McIntyre.