The regular female uniform for secondary student girls in Japan. As any normal girl, Yuuko Asou and her classmates wear it to school daily. Although it isn't of any relevance to the plot, Yuuko starts most of the games either with this or the Pajama suit before obtaining the Valis armor once again.
The Sailor student uniform appears in all the versions of Valis I, Valis II and Valis SD as the first suit (or one of the first) that Yuuko uses. Reiko Kirishima also uses it in Valis I. It also appears in the beginning cutscenes of Valis III and Valis X, and in Yuuko's flashback scene in Valis IV. Yuuko and Reiko also wear it in all the manga adaptions of Valis.
- The Sailor student uniform became a popular cliche in most female anime characters from those years, mostly worldwide thanks to the famous Sailor Moon series. That's why most people outside from Japan frequently confused Valis to be inspired in Sailor Moon when introduced to the series.
- Although Yuuko is mostly known and portrayed with her school uniform in the artworks, she only wears it in the first two games of the series.
- Yuuko has two types of Sailor uniforms, one with long sleeves and one with short sleeves, the first being used in Valis I and the second in Valis II. This variation is probably for use depending on weather or time of year, much like the Blazer uniform.