Mozirje (pronounced [mɔˈziːɾjɛ]; German: Prassberg[2]) is a small town on the Savinja River in northern Slovenia.

The area is part of the traditional region of Styria.

[3] Mozirje was mentioned in written sources in 1146 as Mosiri (and as Prossperch in 1231, Moziri in 1241, and Prasperch in 1391).

The name is derived from the Slovene common noun mozirje 'swamp' and refers to the local geography.

[2] The parish church in the town is dedicated to Saint George (Slovene: sveti Jurij) and belongs to the Roman Catholic Diocese of Celje.