Leo Cullen’s side crossed for six tries at the Stadio Comunale di Monigo, two of them for Dave Kearney, who was returning from an ankle injury.
Adam Byrne touched down for the fourth bonus point try early in the second half.
Leinster scored a try in the opening moments when Rory O’Laughlin collected Ross Byrne’s chip over the top and slid over. Ross Byrne converted. And Kearney added his two tries before the hosts registered on the scoreboard. The Ireland winger, starting for the first time since October, scored out wide after Dominic Ryan’s initial break in midfield.
Kearney again went over in the corner soon afterwards and Ross Byrne added another conversion to make it 21-0.
Robert Barbieri and winger Andrea Pratichetti scored either side of half-time for the hosts, the latter’s try coming after Adam Byrne had finished following a powerful Leinster scrum. Ross Byrne again converted.
Joey Carbery, also back from injury, had a near instant impact after coming off the bench, burrowing through to score.
And Bryan Byrne went over for a sixth Leinster try following a driving maul.
Tries: Paulo, Pratichetti. Cons: McKinley 2.
Tries: O’Loughlin, D. Kearney 2, A. Byrne, Carbery, B. Byrne. Cons: R. Byrne 5.
Sperandio, Pratichetti, Iannone, Sgarbi, Buondonno, McKinley, Tebaldi, Zani, Bigi, Pasquali, Gerosa, Paulo, Lazzaroni, Budd, Barbieri.
Benettin for Iannone (71), Tagicakibau for Buondonno (63), de Marchi for Zani (53), Giazzon for Bigi (53), Zanusso for Pasquali (67), Zanini for Barbieri (67).
Kirchner; A. Byrne, O’Loughlin, Reid, D. Kearney, R. Byrne, Gibson-Park, Dooley, Strauss, Bent, M. Kearney, Nagle, D. Ryan, Leavy, Conan.
B. Daly for Reid (63), Carbery for R. Byrne (54), L. McGrath for Gibson-Park (63), Porter for Dooley (56), B. Byrne for Strauss (56), Ross for Bent (56), Molony for Nagle (63), Timmins for Leavy (69).
Daniel Jones (Wales).