It was located in the southern part of the present-day municipality of Valle in the traditional region of Setesdal in Agder county.

The administrative centre was the village of Rysstad where the Hylestad Church was located.

The first element is the genitive case of the word hylr which means "deep place" or "pool in a river".

The last element is the plural form of staðr which means "place", "homestead" or "abode".

[5] The municipal council (Herredsstyre) of Hylestad was made up of 13 representatives that were elected to four year terms.