They'll take on Camross in two weeks time.
The Harps have reached their first Laois Hurling Final since 1998.
They defeated reigning champions Clough Ballacolla yesterday by 4-16 to 2-19, with Eoin Delaney scoring a hat-trick of goals to help his side over the line.
Despite Stephen "Picky" Maher leading Clough/Ballacolla's comeback with 2-7, including a penalty, his side saw their three in a row dream come to an end.
Eoghan Murphy's long-range effort in injury time ended up in the net to seal their place in the decider against Camross.
The Harps Coach, Brian Carroll says luck was on their side in the end:
Brian Carroll spoke to Jack Nolan after the game:
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