The Viola are now winless in six matches at the Artemio Franchi stadium - a run stretching back to March 4 - following today's lacklustre showing.
And it could have been worse had goalkeeper Norberto Neto not pulled off a marvellous save to deny Radja Nainggolan in the closing stages.
Neto's stop also denied Cagliari from claiming a first win on the road since they beat Catania 1-0 on December 4.
The visitors certainly started well in a game that was memorable because of several poor finishes.
Lorenzo Ariaudo and Thiago Ribeiro both missed the target with their long-range strikes and it was a similar story at the other end, with Houssine Kharja firing over from distance.
Alessio Cerci did go close for Fiorentina, with his strike from just outside the area narrowly missing the left-hand post.
It was perhaps the best chance of the half but Cagliari midfielder Nainggolan did test Neto, who made a comfortable save.
Cagliari, looking to end a run of two straight defeats that had seen them drop to 16th, came out firing after the interval.
Ribeiro only just missed the right-hand post with his strike from inside the area, while the striker headed wide soon after.
Ribeiro turned provider to tee up Anderson Nene, who also failed to find the target with his header.
Cagliari continued to press and Nainggolan's strike from inside the area looked destined for the corner but it was well saved by Neto to ensure Fiorentina claimed a point.