The draw was made live on Sky Sports on Thursday evening and, after Mick McCarthy picked out Forest, former Magpie Chris Waddle selected ball number 17 to give his old club a trip to the City Ground.
The two sides last met in the same stage of last season's competition, but at St. James' Park. Despite taking the lead through Aleksandar Mitrovic - and a wonderful goal from Rolando Aarons - United lost 3-2 after extra time.
However, Newcastle were 4-3 victors after extra time in a third round tie at Forest in 2011/12, with Fabricio Coloccini scoring a dramatic late winner.
And when the sides faced each other in another second round tie in 1974/75, they drew 1-1 at the City Ground before Newcastle won 3-0 in the St. James' Park replay.
Daryl Murphy and Jack Colback, who were part of United's 2016/17 Sky Bet Championship title-winning squad, are both now with Forest - the latter on a season-long loan from Newcastle.
Meanwhile Magpies skipper Jamaal Lascelles and goalkeeper Karl Darlow both began their careers with Forest.
The tie will be played in the week commencing Monday, August 27th and full details will be confirmed shortly.