The game, which took place at the Artemio Franchi stadium in Florence, ended 4: 3 in favor of the violets.
For Fiorentina, the goals were scored by Joseph Alfred Duncan (15th minute), Riccardo Saponara (45th), Dusan Vlahovic (60th, 85th).
At Milan, Zlatan Ibrahimovic (62nd, 67th) scored a double, Lorenzo Venuti (90th) - an own goal.
Milan (32 points) are in second place in the standings.
Fiorentina (21) are in sixth position.
Earlier it was reported that Atalanta defeated Spice in a Serie A. match.