The Brazilian boy used makeshift skateboarding facilities in his grandmother's garden to practice before pulling off the feat.
More than 20 years after US skateboarding legend Tony Hawk completed the world's first 900-degree spin, Gui Khury completed three full rotations on his board before a clean landing.
The trick has been seen as one of the "holy grails" in the sport.
He pulled off the historic feat using makeshift skateboarding facilities in his grandmother's back garden as he trained during the coronavirus lockdown.
Posting a video of his achievement on Facebook, Gui said: "1080!!!I have no words to explain what just happened."
"He has an opportunity to train here, if he didn't have (the skate facilities)... he would be stuck at home like everyone else and unable to do sport. So the isolation helped him focus."
Gui had already become the youngest person to complete the 900-degree spin, which he did aged eight.
He added that his celebration meal was "mac and cheese at home" with his family.
During the closing of schools in Brazil, the boy's family have been making an almost-daily short journey to his grandmother's home to drop off food, as well as use the skate ramp.
Hawk was 31 when he completed the world's first 900-degree spin in 1999 - about a decade before Gui was born - and only a handful of skaters have pulled it off since.
The 11-year-old's move was uploaded to Instagram by his parents, with Gui saying he sent the clip to some of his idols, such as Hawk and Bob Burnquist.
"Some posted it on their stories and some actually posted it on their Instagram. I was like that's so crazy, because it's like a once in a lifetime experience.
"It's so amazing. It's the best feeling ever," he said.
Gui said he wants to keep practising his triple spin so he can use it in competitions, and work towards a 1260-degree version.
https://news.sky.com/story/gui-khury-skateboarder-11-makes-history-by-landing-1080-degree-spin-on-vertical-ramp-11986346