Enda Kenny’s position as leader was secured by the strong showing, despite his failure to become Taoiseach.
The 4% swing takes the party back to its position after defeat in the 1997 election, before the devastation of the 2002 rout.
FG re-asserted itself as the driving force of anti-FF opinion as the minor parties and independents were smashed out of the way.
Mr Kenny insisted the party had done “outstandingly” well.
“You can’t argue with the message of the people. From our point of view gaining 20 seats is an outstanding success,” he said, refusing to concede defeat until fuller results were in.
Fine Gael made a strong performance across the capital with first time candidate Lucinda Creighton regaining Garret FitzGerald’s old seat in Dublin South East.
It was a similar picture across the country as the party saw its share of the vote rocket by 25% in Clare and re-took seats in Donegal, while Brian Hayes avenged his 2002 defeat by being elected in Dublin South West.
FG was also putting up a determined battle for the final berth in Taoiseach Bertie Ahern’s heartland of Dublin South Central as the Sinn Féin challenge failed to materialise.
High-profile candidate Leo Varadkar swept to victory in the bitterly fought Dublin West constituency where the FG showing saw Socialist TD Joe Higgins dumped from the Dáil at his expense.
The party was also on course to oust PD TD Tom Parlon in Laois-Offaly and FG was poised for three seats in Mayo where Mr Kenny brought in a major personal vote. However, some of the expected successes failed to materialise for FG with big name candidates like Mairéad McGuinness missing out in Louth.
A member of the opposition frontbench Denis Naughten was also having a tough time of it.
As the traditional two-party system came back to the fore, Rainbow partners Labour suffered, losing out in at least three constituencies due to the surge for Mr Kenny’s party.
Fine Gael rules mean Mr Kenny can now be challenged for the leadership after failing to become Taoiseach.
However, it is unlikely anyone from the opposition frontbench would stand against him, but critics like Waterford TD John Deasy may be persuaded to force a contest.
Fine Gael was left with just 31 seats in 2002 after gaining 54 at the previous 1997 election.