The Vietnam U-20 squad was placed in Group E alongside France, Honduras and New Zealand.
The ROK is in Group A together with Guinea, Argentina and England.
Venezuela, Germany, Vanuatu and Mexico are in Group B; Zambia, Portugal, Iran and Costa Rica (Group C); South Africa, Japan, Italy and Uruguay (Group D); and the USA, Ecuador, Saudi Arabia and Senegal (Group F).
The final rounds of the Fifa Under-20 Cup are set for May 20-June 11 in the ROK.
VOV