New Zealand will stage the 2014 IRB Junior World Championship (JWC) and Italy the 2015 edition, the global governing body announced.
The 2014 tournament will be the first time the competition has been staged in New Zealand, which last year saw its beloved All Blacks win the Webb Ellis Cup on home soil.
By contrast 2015 will see the JWC returning to Italy after the 2011 edition was staged in the Veneto Region.
New Zealand won the U20 title four times in succession and will hope to reclaim the crown they lost to hosts South Africa in 2012, in order to welcome the world's rising stars to their shores as defending champions in 2014.
The 2013 edition is due to be staged in northern France.
"We proved to the world last year how well we as a nation could deliver a complex global sporting event and I am sure we will again deliver an excellent tournament that does the country proud," said New Zealand Rugby Union chief executive Steve Tew.
Matches will be played in the Auckland region, at North Harbour Stadium in Albany and in Pukekohe. Eden Park, which staged last year's World Cup final, is also being considered as a possible venue for the final.
Meanwhile Federazione Italiana Rugby (FIR) president Alfredo Gavazzi hoped staging the 2015 edition, just months before that year's Rugby World Cup in England, would help give Italian rugby a boost.
"To host again the IRB Junior World Championship in Italy in 2015 is a great honour and privilege for us," he said.
"The 2011 tournament in the Veneto Region was very successful and proved how rugby has grown in our country at all levels of the game."