Indonesia were originally scheduled to host the tournament but were stripped of the hosting rights last month.
The move came about after a top Indonesian official objected to the participation of Israel.
Indonesia have no diplomatic ties with Israel.
Argentina are the new beneficiaries after FIFA confirmed on Monday that the South Americans will take the place of Indonesia.
FIFA president Gianni Infantino said in a statement: “FIFA is delighted to announce that this year’s edition of the FIFA U-20 World Cup will take place in Argentina, as the home of the world champions opens its doors to the tomorrow’s superstars of world football.
“I would like to thank the AFA and particularly its President Claudio Tapia, as well as the governmental authorities, for their commitment to hosting this magnificent event at such short notice.
“The U-20 World Cup plays a key role in FIFA’s efforts to promote youth football across the world. Since 1977, this tournament has featured some of the greatest players of the past decades, including Diego Armando Maradona, Lionel Messi, Paul Pogba, Erling Haaland and many others. Having this year’s edition taking place in a country that lives and breathes football will be a tremendous inspiration for the stars of tomorrow.”
The draw for the tournament will take place in Zurich on Friday.
The tournament is due to be held from May 20 to June 11.