Another Saffa set to play for Scotland
Miller, who qualifies for Scotland through his mother, plays for Watsonians, based in Edinburgh.
The 19-year-old loose forward has also represented Scotland at U19 level.
Whilst at school, Miller played for Kearsney’s first XV for two years and was also selected for the Sharks Craven Week team in 2016.
The 28-man squad, which consists of 16 forwards and 12 backs, includes 18 players who’ve progressed through the Sport Scottish Rugby Academy, while only eight players, including Miller, were not involved in the U20 Six Nations campaign earlier this year.
Scotland U20 Head Coach, Bryan Redpath, said: "We’ve chosen a versatile and combative squad, who’ve really grown together after their experiences in the recent Six Nations campaign.
"We’re really eager to get started in a few weeks time and I’m looking forward to playing a role in the development of this strong squad,"
The World Rugby U20 Championship, hosted by France, takes place between May 30 and June 17.