The Sarmatic mixed forests constitute an ecoregion within the temperate broadleaf and mixed forests biome, according to the World Wide Fund for Nature classification (ecoregion PA0436).^[2][3] The term comes from the word "Sarmatia".

This ecoregion is situated in Europe between boreal forests/taiga in the north and the broadleaf belt in the south and occupies about 846,100 km² (326,700 mi²) in southernmost Norway, southern Sweden (except southernmost), southwesternmost Finland, northern Lithuania, Latvia, Estonia, northern Belarus and the central part of European Russia.^[4]

It is bordered by the ecoregions of Scandinavian and Russian taiga (north), Urals montane tundra and taiga (east), East European forest steppe (southeast), Central European mixed forests (southwest) and Baltic mixed forests (west), as well as by the Baltic Sea.

The ecoregion consists of mixed forests dominated by Quercus robur (which only occasionally occurs farther north), Picea abies (which disappears further south due to insufficient moisture) and Pinus sylvestris (in drier locations). Geobotanically, it is divided between the Central European and Eastern European floristic provinces of the Circumboreal Region of the Holarctic Kingdom.

• Stockholm - Swamp in a sarmatic mixed forest.
• Norway - Winter in the beech forest in Larvik, Norway. Aside from conifers, black alder, white birch and elm are more common in the Sarmatic mixed forest.
• Coniferous trees in southernmost Finland dominate this Sarmatic mixed forest.
• South Estonia - Deciduous and coniferous trees clearly differentiate on this springtime photo.