Katie Douglas scored 21 points, and the 62 win over New York in the deciding third game of the their Eastern Conference semifinal series.
Tamika Catchings added 17 points and eight rebounds for Indiana, which will host Atlanta in the best-of-three East finals, starting Thursday at Conseco Fieldhouse. The Dream went 4-0 this season against the Fever.
Erin Phillips scored 12 in the victory, as the Fever forced 20 turnovers, leading to 26 points.
Nicole Powell had 19 points and Cappie Pondexter added 11 for the Liberty, who protected home court on Saturday to force a winner-take-all Game 3.
Pondexter's layup had the visitors within 57-54 with 5:50 left in the game, but Indiana scored the ensuing 11 points. Jessica Davenport sank two free throws to start the rally, Catchings nailed a three-pointer and a layup before two free throws from Douglas and her running bank shot with 1:44 remaining made it a 68-54 margin.
The Liberty led by as many as six in the second quarter, but seven straight points from the Fever gave them a 24-23 edge. They were up 40-36 at the half and scored the opening nine points of the third. It was 54-48 moving to the fourth.
This is the second time in three years the Fever have reached the East finals. In 2009, they made it to the WNBA Finals before falling to Phoenix in five games.