Vincenzo Montella's men were chasing a first win in five games to restore their bid for a Champions League place and veteran striker Luca Toni put them on track with his ninth Serie A goal against Parma.
And the visitors, who are sliding down the league table, were condemned to a second straight defeat when Stevan Jovetic scored five minutes into the second half.
Fiorentina poured forward in pursuit of an early goal, Giulio Migliaccio powering a header wide of the target before Toni saw his glancing effort deflected behind by Gabriel Paletta.
Parma flirted with turning the tables on their hosts and Alessandro Lucarelli soon sent Emiliano Viviano sprawling with a treacherous headed effort.
La Viola would dominate the first half, though, and Migliaccio was only denied a 13th-minute opener thanks to his rough treatment of visiting goalkeeper Antonio Mirante.
Massimo Gobbi kept the Gialloblu alive, albeit briefly, when he cut out Manuel Pasqual's diagonal pass to an unmarked Borja Valero, but Fiorentina would make the breakthrough in the 27th minute.
Toni continued his regular torment of Parma by nodding home his seventh goal of the season thanks to a fine cross from Juan Cuadrado.
That goal sparked Parma into life and Jonathan Biabiany seemed particularly keen to make a difference, the winger bursting through the backline to find Nicola Sansone, whose shot and rebound were both smothered by Viviano.
Sansone repeated Biabiany's trick to skip past Gonzalo Rodriguez and tee up a shooting chance, but the end product was sorely lacking.
The renewed spirit would not carry through to the second half, however, and Fiorentina doubled up within five minutes of the restart.
A perfect series of passes carried Pasqual's cross through to Migliaccio, who rolled the ball over for Jovetic to put the finishing touch on the move.
Cuadrado came dangerously close to a quickfire third, instead shooting wide, but there was no question about who wanted the points more.
Toni had the ball in the back of net again with 66 minutes played, thanks to good work from Jovetic, but the linesman's flag spared Parma further embarrassment.
Try as they might, there was nothing the Gialloblu could do to turn the tide and a wayward header from Biabiany just inspired further applause from the Tuscan crowd.