Ireland ran in four tries and barely missed their British & Irish Lions stars as hosts Japan were brushed aside in Osaka.
Tries from Tommy Bowe, Kevin Maggs, Frankie Sheahan and Simon Best destroyed the home side, whose points all came from the boot of Kyohei Morita.
David Humphreys kicked eight early points for the tourists, with replacement Jeremy Staunton then taking up duties and adding a further 16 to Ireland's score.
Ireland were quick to impose themselves on the contest, Humphreys putting them 6-0 ahead after eight minutes, and the opening try from Bowe in the 14th minute allowed the lead to extend to 13-3.
With centre Maggs crossing in the 24th minute, Ireland's half-time lead stood at 26-9, just the sort of scoreline they had been hoping for.
Niall O'Donovan, standing in as coach for Eddie O'Sullivan who is on Lions duty in New Zealand, knew that his side were overwhelming favourites to win the match, and by a wide margin.
O'Donovan had stressed before the match that Ireland would pay their opponents due respect despite the huge gulf in class.
But that did not mean there was any letting up in the second half of what represented Ireland's first full Test on Asian soil.
Two penalties in quick succession from Staunton stretched the lead to 32-12, however he then failed with the conversion attempt after Sheahan touched down for Ireland's third try in the 57th minute.
Best put the seal on victory in the 69th minute with his first international try, Staunton making no mistake this time by slotting the extras.