"First relocations within EU take place on Friday" following an agreement by interior ministers in September, the EU's home affairs office said in a tweet. "Eritrean refugees will be relocated from Italy to Sweden."
An EU source told AFP that a flight will leave Roma Ciampino airport in the morning and take the first refugees to Sweden.
EU Migration commissioner Dimitris Avramopoulos is expected to give a press conference in Rome.
The number of refugees being moved on Friday was not revealed, but Sweden agreed on July 20 to take 821 refugees from Italy and 548 from Greece as part of the commission's plan to relocate 40,000 refugees from the two frontline states over two years.
The EU formally agreed the plan last month despite the opposition of some eastern European states worried about a popular backlash to migrants.
Until now, member states have only agreed to redistribute 32,000 people but are expected to make up the difference by the end of the year.
With the crisis worsening, the EU has agreed to relocate a further 120,000 after overriding opposition from the same eastern European states.