An engrossing game in wet conditions saw the Cats defeat Limerick by 2-13 to 0-17, thanks to goals from Richie Hogan and a crucial second-half effort from Eoin Larkin.
That completed the double for Kilkeny, who also won the All-Ireland Minor Hurling Semi-Final.
They defeated Waterford by 1-23 to 1-14 after extra-time in the opening game at Croke Park.
