Seb Stegmann, Hugo Ellis, Luke Eves, Matt Cox, Nathan Catt, Mark Odejobi and Noah Cato all scored sparkling tries, four of them converted by Alex Goode (Saracens).
A combative Ireland side were well in the game in the first half.
David Kearney scored early on for the visitors and fly half Ian Madigan kept Ireland well in the game with three first-half penalties.
But ultimately they didn’t have England’s pace and firepower.
Overcoming a tough Ireland side, who had conceded fewer points than the hosts going into this game, was no easy task, emphasised when England fell behind after four minutes, full back Kearney finding no-one at home when put through a gap 40 metres out.
The lead lasted less than three minutes, though, when Ellis battering his way to within inches of the line and the ball released for Goode to put Stegmann over for his second try of the campaign and convert from wide on the right.
But Ireland were still on the offensive, and went ahead when Madigan stroked over his first successful penalty effort.
It took until the half-hour mark for England to rediscover some sparkle, with a sweeping long-range attack down the right involving Simpson, Greendale and Cato before Stegmann put Ellis away for the second try with Goode again converting.
Another careless penalty conceded at the kick-off allowed Madigan to get Ireland back to 14-11 down but England produced another sharp attack from long-range to nail their third try four minutes before the break.
This time it was Odejobi who broke tackles and Cato blasted his way toward the left-hand corner before offloading for Eves to score.
Madigan added a third penalty just before the interval to keep Ireland in the game and England holding a five-point lead.
Andy Saull replaced England captain Ellis for the second half.
Fisher, who switched to number eight, broke tackles down the left and Cox was rewarded for his support run with a score after the play was reviewed by TMO Andy Ireland.
England’s celebrations could really begin when Cato seized on Goode’s inside ball and blasted his way past three covering defenders to claim his sixth try in five games this season.
And suddenly there were runners coming from everywhere, another Greendale and Goode combination taking England close and loose-head Catt ploughing over from close range 10 minutes from time.
Ireland got on the front foot for a brief spell but they couldn’t prevent England attacking from deep and Odejobi outstripped the cover to finish a length-of-the-field counter-attack five minutes from time.
ENGLAND U20: N Cato (Saracens); S Stegmann (Harlequins), L Eves (Bristol Rugby), A Goode (Saracens), M Odejobi (London Wasps); A Greendale (Leeds Carnegie), J Simpson (London Wasps); N Catt (Bath Rugby), J Gray (Northampton Saints), A Corbisiero (London Irish), G Kitchener (Worcester Warriors), S Hobson (Cornish Pirates), J Fisher (London Irish), M Cox (Worcester Warriors), H Ellis (London Wasps, captain).
Replacements: S Freer (Leeds Carnegie) for Gray 68, B Moss (Bath Rugby) for Corbisiero 68, J Cannon (Northampton Saints) for Kitchener 53, A Saull (Saracens) for Ellis 41, B Youngs (Leicester Tigers) for Simpson 68, G King (Worcester Warriors) for Saull 71, D Norton (Gloucester Rugby) for Stegmann 70.
IRELAND U20: D Kearney (Leinster); S Scanlon (Munster), E O’Malley (Leinster), C Cleary (Leinster), C Cochrane (Ulster); I Madigan (Leinster), D Moore (Leinster); P Karayiannis (Ulster), J Harris-Wright (Leinster), B Barclay (Leinster), D Nolan (Connacht), E Sheriff (Leinster), K Essex (Munster), P Ryan (Leinster, captain), P Mallon.
Replacements: S Douglas (Ulster) for Harris-Wright 65, S Archer (Munster) for Barclay 65, T Conneely (Connacht) for Essex 46, I Porter (Ulster) for Moore 47, M Dufficy (Leinster) for Madigan 47, E Sheridan (Leinster) for Cochrane 73.
Referee: N Paterson (SRU)