It could have been an even better result for the Blucerchiati, who led through Elio De Silvestri's first-half goal, but Nicolas Spolli earned the Sicilians a share of the spoils midway through the second half.
Catania, who had long since secured their top-flight status for another season, improved on what has already been a record-breaking season, although they are now out of the running for a place in the Europa League next season.
Former Catania forward Maxi Lopez was given a rare start in the Samp starting XI and he almost set up an opener for the Genovese side in the seventh minute, but Renan Garcia failed to make the most of the chance.
At the other end, Gonzalo Bergessio tested Angelo Da Costa, who made the first save of the night as the linesman's flag was raised.
Lopez then set up Eder for another chance, but he like Renan before him let the chance get away.
Samp were nevertheless looking lively and they took went close to scoring again in the 34th minute when Lopez this time chose to go it alone, but his shot was saved well by former Genoa goalkeeper Alberto Frison.
Just two minutes later, Samp took a deserved lead when De Silvestri headed in Renan's left-wing cross.
Lopez, always in the thick of the action, tried to make it two with another individual effort in the 65th minute, but Frison denied him once again.
Catania then levelled out of the blue with Francesco Lodi's free-kick met by Bergessio, who touched the ball across for Spolli to head in to an empty goal.
Samp responded with Gianluca Sansone hitting the post and De Silvestri's shot taking a deflection on its way just wide of the post.
But as the news came through that Palermo had been beaten at home, and that a draw would be enough to keep Samp up, the celebrations started inside the Stadio Luigi Ferraris as the final whistle blew.