The 86-year-old collapsed and died on Friday afternoon but the cause of his death has not yet been determined.
He had been cast as Ser Denys Mallister, the eldest member of the Night’s Watch, and producers of the hit HBO show have announced they won’t be recasting his part.
Creators DB Weiss and David Benioff told The Independent: “We will not be recasting JJ Murphy.
“He was a lovely man, and the best Denys Mallister we could have hoped for. And now his watch is ended.”
The veteran actor had also appeared in Angela’s Ashes and the upcoming Dracula Untold, in which he plays a village elder.