Prowse, the Bristol weightlifter-turned-actor who played the villainous Sith lord in the original Star Wars trilogy, died after a short illness, his agent confirmed.
The towering 6ft 6in performer also earned an MBE for playing the Green Cross Code Man to promote road safety.
Lucas, whose Lucasfilm company produces the space epic series as well as the Indiana Jones films, paid tribute in a message posted on the Star Wars website.
The 76-year-old said: “David brought a physicality to Darth Vader that was essential for the character.
“He made Vader leap off the page and on to the big screen, with an imposing stature and movement performance to match the intensity and undercurrent of Vader’s presence.
“David was up for anything and contributed to the success of what would become a memorable, tragic figure. May he rest in peace.”
A statement from Lucasfilm itself remembered Prowse’s “strongman’s physique” and his performance as Vader where “simple gestures, could convey anger, sadness, and lost hope”.
Prowse’s agent Thomas Bowington confirmed his death in a statement on Sunday, saying: “May the force be with him, always.”
Mr Bowington added: “Though famous for playing many monsters for myself and all who knew Dave and worked with him he was a hero in our lives.
“A constant source of inspiration, encouragement and kindness. A truly and deeply heart wrenching loss for us and millions of fans all over the world.
“But the great power of Prowse in our lives will always stay with us! A loving husband, father and grandfather.”
Mark Hamill, who played Luke Skywalker opposite Prowse, tweeted: “So sad to hear David Prowse has passed. He was a kind man & much more than Darth Vader.
“Actor-Husband-Father-Member of the Order of the British Empire-3 time British Weightlifting Champion & Safety Icon the Green Cross Code Man. He loved his fans as much as they loved him.”
Daniel Logan, who played the young Boba Fett in Attack Of The Clones, recalled meeting Prowse across the years at various Star Wars conventions.
He said on Twitter: “Sad to hear of the passing of a #StarWars family member. RIP Dave Prowse. Darth Vader wouldn’t be the same without you in the costume.
“We had many fun times & laughs at cons together over the years. Glad to have been able to call you a friend. Rest now and be one with the Force!”
The Twitter account of the Peter Mayhew Foundation, set up in memory of the actor who played Chewbacca, shared a picture of Prowse with Mayhew and their co-star Kenny Baker.
“RIP Dave Prowse. I hope you’re up there sharing a pint and a story with the boys. #DarthVader #DaveProwse #RIPDaveProwse #StarWars.”
Mayhew died in 2019, and Baker, who played R2-D2, died in 2016.
Prowse won the role playing Vader due to his impressive physique, but with his West Country accent deemed not quite suitable, the part was instead voiced by James Earl Jones.
He represented England in weightlifting at the Commonwealth Games in the early 1960s before embarking on an acting career.
Prowse was reportedly spotted by Star Wars director Lucas when playing a bodyguard in the 1971 film A Clockwork Orange, and invited to audition for the roles of Darth Vader and Chewbacca.
He once told the BBC he chose Vader over his hairy co-star because “you always remember the bad guys”.
Elsewhere, his career included collaborations with comedy staples such as The Two Ronnies, Kenneth Williams, Morecambe and Wise and Benny Hill. He also appeared in Carry On Henry and Jabberwocky.
In 1972, he appeared as the Minotaur in the Doctor Who episode The Time Monster, opposite Jon Pertwee as the eponymous Time Lord.
Watch: C-3PO star Anthony Daniels pays tribute to David Prowse