Ukraine qualified as one of six nations from Europe, one of a number of surprise UEFA representatives, as traditional heavyweights like Spain, France and Italy missed out.
The United States finished in the top four of the 2015 North American Under-20 Championships to qualify while Myanmar was one of four teams to emerge from last year's AFC Under-19 Championships.
Favourites (and why)
The United States will be expected to top Group A, with Ukraine and New Zealand jostling for the second spot.
The Americans have a well-funded programme and will be supremely organised and athletic, crucial attributes at this level. Their squad is drawn from professional clubs, among them Arsenal, Tottenham, Fulham, LA Galaxy and Boca Juniors. They have had an enviable build-up, including games against Argentina, England, Russia and Chile.
Underdogs (and why)
Myanmar. They can't be completely discounted, as they qualified from Asia and have an experienced German coach but they were undoubtedly aided by hosting the qualification tournament. The White Angels don't have any overseas-based players, with their 23-man roster selected from clubs in the local domestic league.
History (who has done well in the past, or not done well)
The Americans have qualified for eight of the last nine Under-20 World Cups, going beyond the group stages on six of those occasions. Ukraine hasn't featured in this tournament since 2005 while New Zealand have yet to reach the knock-out stages in three attempts (2007, 2011 and 2013). This is Myanmar's first Fifa tournament at any age group level.
Star man
Bill Tuiloma (New Zealand). The Birkenhead United product, now based at Olympic Marseille, will be pulling the strings in midfield for the hosts and could shine at this level. Romain Gall (United States) will also be one to watch, as the French-born striker was a profilic scorer for the Americans in qualifying.
Stat
New Zealand has six overseas-based players, including Tuiloma, Jesse Edge (Vicenza Calcio) and Monty Patterson (Ipswich Town FC). They also have five players based at the Wellington Phoenix. The rest of the team are drawn from the ASB Premiership.
Did you know? United States coach Tab Ramos was the first player signed by Major League Soccer, ahead of the league's launch in 1996. He had a long stint at New York Metro Stars and also played at Real Betis and Tigres (Mexico) during his career. He was also assistant coach to Jurgen Klinsmann at the 2014 World Cup.
The USA will top group A with seven points, with Ukraine second ahead of New Zealand. There'll be no fairytale for Myanmar, who will return home without a win.
Contract boosts keeper
The under-20 World Cup hasn't started yet but already New Zealand goalkeeper Oliver Sail feels on top of the world.
Not only is the 19-year-old loving being in camp with his under-20 international teammates, on Saturday he took another step towards achieving his ambition of playing football for a living.
Sail, who has been training regularly with the Wellington Phoenix first team squad this season and playing for the club's reserve side, signed a two-year contract under the ASB Premiership Contracted Player category which is the equivalent of a National Youth League contract for Australian A-League players.
"It came as a complete surprise and I am really buzzing at the moment," Sail said.
"It doesn't seem real but when I look at the contract I know it is.
"The big thing is that it provides me with security and is a big weight off my shoulders because I want to keep progressing toward being a professional footballer.
"Everything has happened so quickly, but I can now focus on playing good football and the priority is helping the New Zealand team make its mark at the World Cup."
Sail said the team was progressing every day and had performed well in its warm-up games.
"We were a bit unlucky to lose against Honduras and the belief that we can perform well is there," he said.
"I'm feeling confident and training with the Phoenix senior players every day has helped me prepare for this challenge.
"Working with Mossy (Glen Moss) has been fantastic because I believe he is New Zealand's best-ever keeper.
"He is always willing to give me advice and lets me know if I am not doing something well.
"I also owe a lot to goalkeeping coach Jonathan Gould who I worked with till he moved to West Bromwich Albion, and now Des Buckingham is keeping me on my toes."