The anime is set immediately after the main storyline's Sanctuary arc after the defeat of Gemini Saga from Masami Kurumada's original Saint Seiya manga, but before the Posieidon arc. However, whereas the original manga followed a boy named Seiya and other Saints who fight to protect the goddess Athena, the new series follows a female "Saintia" named Shō who fights evil deities to protect Athena.
 
(Source: Anime News Network)

In the wake of a space-wide civil war instigated by Saga–the Gemini Gold Saint–a new team of Saints comes together with the goal of protecting their goddess Athena. This first all-woman team of armored warriors, powered by the Zodiac, will use their cunning, strength, and compassion to defend their worlds and oppose their very destinies. Mangaka Chimaki Kuori is also known for working on manga for Gundam Seed and the Persona series. 
(Source: Seven Seas Entertainment)
 
Note: The chapter count includes 86 regular chapters, 2 "Extra Story" chapters included at the end of volumes 7 and 16, and a prologue and one special chapter that were omitted from collected volume releases.

Katja