The 37-year-old actor, who was already on Facebook, debuted on the photo-and-video-sharing app on Wednesday.
The Oscar-nominated actor captioned his first post: "I just realised I'm not playing Spider-Man."
The funny clip opens with Gyllenhaal reading The Amazing Spider-Man comic, titled 'The Return Of The Man Called Mysterio' and exclaiming, "Whoa! What the f**k?"
Mysterio is the antagonist in the follow-up to the 2017's "Spider-Man: Homecoming".
Gyllenhaal already has over 268k followers and is following 39 people on the social media app.
(This story has not been edited by Business Standard staff and is auto-generated from a syndicated feed.)