The 2023–24 Segunda Federación season is the third for the Segunda Federación, the fourth-highest level in the Spanish football league system.
Ninety teams participated, divided into five groups of eighteen clubs each based on geographical proximity.
In each group, the champions automatically promoted to Primera Federación, and the second to fifth placers will play promotion play-offs.
The last five teams in each group will be relegated to the Tercera Federación; in addition, the four worst teams classified 13th in their group will contest play-offs to define the last two relegation places.
A total of 90 teams joined the league: ten relegated from the 2022–23 Primera Federación, 53 retained from the 2022–23 Segunda Federación and 27 promoted from the 2022–23 Tercera Federación.