It was confirmed last night that Whedon, creator of the long running TV hit Buffy The Vampire Slayer, as well as 2012's Marvel blockbuster Avengers Assemble, will walk the red carpet outside the Glasgow Film Theatre.
Whedon will be in Scotland on February 24 to attend the GFF closing gala film, which is the UK premiere of his version of William Shakespeare's Much Ado About Nothing.
Whedon, 48, will introduce the film and also take part in a short question and answer session about the film, which is in black and white, afterwards.
The "huge following" that Whedon and his works have, the festival said, meant that the screening of Much Ado About Nothing was the first event in the GFF programme to sell out, within an hour of going on sale on January 17, even before the cult director's attendance was confirmed.
In contrast to Whedon's best-known works, the stripped-down Much Ado About Nothing was shot on a small budget in his own house in Santa Monica, California, over a period of two weeks.
Some of the actors will be well known to fans familiar with Whedon's previous work.
The cast includes stars of Buffy The Vampire Slayer, Dollhouse, Firefly, and Clark Gregg from Avengers Assemble.
Allison Gardner, the GFF co-director, said: "We're absolutely thrilled to be welcoming Joss to Glasgow, in a very fitting end to the biggest-ever Glasgow Film Festival programme.
"Much Ado About Nothing is a hilarious, moving and accomplished piece of work.
"It's really exciting to see Shakespeare brought bang up to date by a director with a real feel for language, and we look forward to asking him all about it."
Regis Roinsard, director of GFF's Opening Gala film, the French romantic drama Populaire, is also expected to attend.