Two goals from Wolverhampton starlet Gary Mulligan and a third from Mark Quigley of Millwall saw a facile win for the Republic at the UCD venue.
Both wins will boost confidence in this side ahead of next month's European Championship qualifiers against San Marino, Lithuania and Bulgaria.
Ireland took the lead in the 37th minute when galway United's John Russell cut in from his left wing to cross for striker Quigley who neatly chested into the path of the onrushing Mulligan who didn't break stride in firing home from 20 yards out.
Mulligan doubled the lead on 53 minutes when he fired home at the near post following an excellent run into the area for Debry County's David Cassidy's through ball.
Just a minute later, Millwall's Quigley copperfastened the win with a lob on Norwegian stopper Austbo.
Republic of Ireland: Doyle (Birmingham City); O'Mahoney (Limerick), Deans (Derby County), Flynn (Wolverhampton Wanderers), Freyne (Nottingham Forest); Cassidy (Derby County), Dawson (Leicester City), O'Leary (Luton Town), Russell (Galway United); Mulligan (Wolverhampton Wanderers), Quigley (Millwall).
Subs: O'Connor (Wolverhampton Wanderers) for Russell (half time), Yazdani (Coventry City) and Fullerton (Livingstone) for Mulligan and Dawson (61 mins), Gallagher (Dundalk) for Doyle (74 mins), Tyrell (Leeds United) for Quigley (84 mins).
Norway: Austbo; Andreasen, Gabrielsen, Lindsetmo, Malmo; Asker, Hauger, Johansen, Danielson; Lund, Myklebust.
Subs: Storesund for Lindsetmo (half time), Walde and Ertsan for Hauger and Asker (70 mins), Holmvik for Myklebust (76 mins).
Referee: P Tuite (Dublin).