Charlie Craig, 15, from Derbyshire, was a rider at apprentice level with the GB Cycling Team's Rider Route.
The boy's father, Nick Craig, broke the news on Facebook saying the family's world had fallen apart, Cycling Weekly reported.
British Cycling's programmes director Andy Harrison said the organisation was "devastated by the news".
The teenager won the under-16 National Trophy Cyclocross Series in 2016 and was highly thought of in the cycling world.
Mr Craig, himself a national cyclocross champion, said on Facebook: "Our beautiful lovely little boy Charlie went to sleep but never woke up.
"I don't know what else to write just now, but he will be with his little angel niece."
Many people posted messages on Twitter, including Dame Sarah Storey, winner of 15 Paralympic gold medals, who tweeted: "Devastated to hear the news about Charlie Craig, what a tragic loss."
Mr Harrison, from British Cycling, said: "Charlie was a promising young rider who had his whole life ahead of him.
"Everyone involved with the team is devastated by this news and, naturally, all of our thoughts are with Charlie's family."
It is not known at this stage how he died.
Tributes have been paid to a "promising young cyclist" who died in his sleep on Friday.