Scott Rendell scored either side of half-time to help Luton reach the second round of the FA Cup at the expense of Nuneaton.
Rendell turned home JJ O'Donnell's delivery mid-way through the first half to put the Hatters in front.
Andy Brown came agonisingly close to an equaliser, but his header from James Armson's free-kick hit the post.
And Boro were made to pay when Rendell fired home from the penalty spot after Gareth Dean felled Andre Gray.
Luton's victory sets up a second-round tie at home to Dorchester Town, conquerors of League Two Plymouth Argyle.
VIEW FROM THE DRESSING ROOM
Luton Town manager Paul Buckle told BBC Three Counties Radio:
"Nuneaton had their moments but you expect that in an FA Cup game.
"The great thing for me is the players showed loads of character. We deserved to win the game.
"We must improve on our free-kicks into the box. But I'm delighted for the players because there've been some harsh words [after Saturday's 2-0 defeat by Dartford].
"We let ourselves down on Saturday. I don't think I've said that to the media. But I'm delighted for the 500 Luton supporters who came out and that they can go home happy."