Development of Ilioupoli started around 1924, when Greek refugees from Asia Minor settled there.

Ilioupoli is 6 km (4 mi) southeast of Athens city centre.

[2] It lies at the western foot of the forested Hymettus mountain, which covers the eastern half of the municipality.

Its built-up area is continuous with those of neighbouring suburbs Ymittos, Agios Dimitrios, Alimos and Argyroupoli.

Ilioupoli experiences hot, dry summers and mild, wetter winters.