Leicester will meet Sale Sharks in the Premiership final at Twickenham on 27 May after disposing of London Irish in their semi-final clash at Welford Road.
Leicester (20) 40
Tries: Tuilagi, Ellis, Lloyd 2, Murphy
Cons: Goode 3
Pens: Goode 3
London Irish (5) 8
The Tigers, seeking to regain the crown they last held in 2002, were ruthless in establishing a 20-5 half-time lead.
Alex Tuilagi and Harry Ellis scored tries and Andy Goode kicked 10 points, Oliver Magne going over for Irish.
Leicester put the seal on a crushing victory with second-half tries from Leon Lloyd (two) and Geordan Murphy.
They will head to Twickenham hoping to reverse last season's grand final result, when they were humbled by Wasps.
The Exiles, meanwhile, despite seeing their run of nine successive away victories end abruptly, can reflect on a season of tremendous progress.
Goode missed with his opening penalty attempt but rewarded Leicester's early endeavour with a successful shot at goal in the sixth minute.
The Exiles were already struggling for a foothold in the match when scrum-half Paul Hodgson was yellow-carded for trampling on the head of his opposite number Ellis.
Ellis took full advantage of his absence in the 15th minute, putting Tuilagi over in the left corner for the opening try, Goode converting from the touchline.
Mike Catt (right) and Irish had a frustrating afternoon
The visitors were not helped by their lack of a frontline kicker, fly-half Riki Flutey woefully slicing his first penalty attempt.
But with Hodgson back on, it was Irish who enjoyed a man advantage after Tigers lock Ben Kay was sent to the sin-bin for a line-out offence.
They immediately kicked a penalty to the corner, and from Dominic Feau'nati's burst and off-load, Magne plunged over in the left corner.
Irish were grateful to wing Sailosi Tagicakibau for a try-saving tackle moments later which knocked the ball from Tom Varndell's hands as the Tigers wing was set to dive over.
But their defences were breached again on the half-hour when Ellis skipped inside prop Richard Skuse, past Hodgson and surged away for a superb individual try.
Goode's conversion made it 17-5, and he added a thumping long-range penalty with the last kick of the half to give the Tigers a commanding interval lead.
Captain Martin Corry and Ellis were both forced off with head cuts on the resumption, but Leicester made light of their absence.
Mike Catt did land a penalty for Irish but Goode's third kept the visitors at arms' length before the Tigers put the outcome beyond doubt.
Lloyd, barely a minute after replacing Varndell, intercepted Catt's ambitious long pass to sprint 70m up the touchline for their third try just before the hour.
Seven minutes later, Murphy surged onto an Ellis box-kick, kicking the ball into his own hands before diving over.
There was still time for Lloyd to claim his second before the game ended in a flurry of fists, but any resistance from Irish had long subsided.
Leicester: Murphy, Tuilagi, Smith, Gibson, Varndell, Goode, Ellis; Rowntree, Chuter, White, Cullen, Kay, Jennings, Moody, Corry (capt).
Replacements: Healey (for Ellis, 41-52, 71), Johnson (for Corry, 42-55), Lloyd (for Varndell 58), Buckland (for Chuter, 61), Vesty (for Tuilagi, 70).
Not used: Holford.
London Irish: Armitage, Ojo, Catt (capt), Feau'nati, Tagicakibau, Flutey, Hodgson, Hatley, Russell, Skuse, Casey, Roche, Danaher, Magne, Leguizamon.
Replacements: Paice (for Russell, 45), Kennedy (for Magne, 55), Murphy (for Leguizamon, 61), Tiesi (for Feau'nati, 61), Everitt (for Tagicakibau, 74), Willis (for Hodgson, 74).
Not used: Warren.
Referee: Dave Pearson (RFU)