The Ščavnica (pronounced [ˈʃtʃaːu̯nitsa]; German: Stainz) is a 56 km river in Styria, Slovenia. It sources near Zgornja Velka and flows along the Slovene Hills towards the southeast. It passes Negova Castle and Sveti Jurij ob Ščavnici, traverses Lake Gajševci (Slovene: Gajševsko jezero) and the town of Ljutomer, and finally joins the Mura River in Razkrižje.
The Ščavnica is one of the most heavily polluted rivers in Slovenia.
Coordinates: 46°31′N 16°12′E / 46.517°N 16.200°E