Sean Longstaff and Jamaal Lascelles were also on target in an impressive performance from Steve Bruce's side at Easter Road, but it was Brazilian forward Joelinton who stole the show with an excellent performance as well as his well-taken goal against the Scottish Premiership side, whose league campaign begins on Saturday.
The new number nine led the line superbly all evening; his first touch and hold-up play was exemplary, he was a constant threat in behind, and he was involved in Longstaff's strike as well as finding the target himself.
He was in the thick of it almost right from the off, as he nearly got on the end of a low Javier Manquillo cross only for a last-gasp clearance to deny him.
Hibs then took the lead in the ninth minute, when Stevie Mallan smashed the ball home from the edge of the area, with Karl Darlow left helpless.
When Matt Ritchie limped off soon afterwards, it looked like it could be a tough night for the Magpies but Bruce's side responded well and in the 14th minute, Miguel Almirón headed just wide from a wonderful Jonjo Shelvey cross.
Then, from another inviting Manquillo delivery, Joelinton slid in to equalise with what United will hope is the first of many goals in black and white.
A 20-yard strike from the home side's Joe Newell deflected off Longstaff and looped over the crossbar, but from that moment on it was all Newcastle in the first half. Fabian Schär fired a shot just over before Longstaff saw a low cross cut out - and almost turned into his own net - by Paul Hanlon as Almirón waited to pounce.
The Paraguayan saw a penalty saved at Preston on Saturday and still awaits his first Magpies goal, and he was thwarted again in the 24th minute. He raced through on goal but saw his effort blocked by goalkeeper Ofir Marciano.
United kept the pressure on, with Isaac Hayden seeing a shot nudged wide by Tom James after great work from Joelinton and Longstaff, then Longstaff saw an effort deflected over the bar before skipper Lascelles stabbed wide from a Shelvey centre.
Eventually it paid off, with Schär playing the ball up to Joelinton before the ball fell to Longstaff, who rifled past Marciano from 22 yards.
More great work from Joelinton saw him tee up Almirón, whose shot was blocked - by a Hibernian hand, according to the Paraguayan - before the Brazilian was again involved as he weaved through the home defence before appearing to be brought down in the penalty area, but referee John Beaton waved his appeals away.
Joelinton came off to a standing ovation from the travelling fans in the 69th minute and within a minute, United had their third as Lascelles stole in to head a delicious left wing cross from Rolando Aarons past substitute keeper Chris Maxwell.
Fraser Murray saw a 79th minute effort comfortably fielded by Darlow, who had earlier made a good save from Oli Shaw, but Newcastle were able to comfortably see out the final few minutes to record their second victory of a pre-season campaign which ends with a home game against Ligue 1 side Saint-Étienne on Saturday.
Hibernian: Ofir Marciano (Chris Maxwell 46), Paul Hanlon (c) (Scott Allan 46), Vykintas Slivka (Adam Jackson 46), Joe Newell (Steven Whittaker 46), Stevie Mallan (Josh Vela 46), Tom James (Daryl Horgan 46), Florian Kamberi (Christian Doidge 46), Darren McGregor (Ryan Porteous 67), Oli Shaw (Josh Campbell 81), Fraser Murray (Jamie Gullan 81), Sean Mackie (Josh Doig 90)
Subs not used: Ben Stirling
Newcastle United: Karl Darlow; Javier Manquillo (Jamie Sterry 77), Fabian Schär (Federico Fernández 77), Jamaal Lascelles (c), Paul Dummett (Ciaran Clark 71), Matt Ritchie (Rolando Aarons 11); Isaac Hayden, Jonjo Shelvey (Matty Longstaff 77), Sean Longstaff (Ki Sung-yueng 60); Miguel Almirón (Jacob Murphy 69); Joelinton (Yoshinori Muto 69)
Sub not used: Freddie Woodman
