Former Belgium boss Tedesco took over from Jose Mourinho in September but has failed to see out the season.
A 3-0 loss at Galatasaray on Sunday all but ended Fenerbahce's hopes of winning a first Super Lig title since 2014, leaving them seven points behind their city rivals with three matches remaining this term.
The bad-tempered match saw Fenerbahce midfielder Talisca miss a first-half penalty with the game goalless, while goalkeeper Ederson was sent off in the second period.
Fenerbahce said in a statement that sporting director Devin Ozek and football coordinator Berke Celebi had also been fired, with assistant coach Zeki Murat Gole to replace Tedesco until the end of the campaign.