Replacement wing Will Hurrell claimed two tries, with Joe Cobden, Gareth Clarke and Manu Tuilagi joining him on the scoresheet. Elliott Read and George Ford claimed one conversion each.
Tigers led 12-0 at half-time before stretched their advantage in the second half and claiming a hat-trick of victories over the Welsh this season after previous wins against Cardiff and the Ospreys.
Greig Tonks made his return from injury at full-back, while Calum Green returned at lock after an ankle injury.
The Academy visit Leeds Carnegie on Saturday and then host Ospreys Under-18s at Oval Park on Wednesday, November 12 (7.15pm).
Leicester Tigers Academy: Greig Tonks, Manu Tuilagi, Joe Cobden, Gareth Clarke, Alex Lewington, Elliott Read, Sam Harrison; Jonny Harris, Jimmy Stevens, Ryan Bower, Calum Green, Mark Deaville, Seb Pearson, Matt Everard, Tom Armes. Reps: Finlay Barnham, George Ford, Will Hurrell, Andy Gates, Huw Marsden, Jethro Rawling