The Laois side defeated Naomh Mairtín away from home.
Portarlington are just one win away from a Leinster Football Final appearance.
Pat Roe's side saw off Louth side Naomh Mairtín by 0-14 to 1-8 in the quarter finals to seal a place in the final four of the provincial championship.
Colm Murphy and Daragh Galvin finished with 0-4 each.
The Laois side will take on Kildare champions Athy in two weeks time after they were too strong for Meath's Summerhill on Saturday evening.
Roe says his side put in a strong 60 minute performance:
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