Marsbäcken is a village in Västervik Municipality, in Kalmar County, Sweden. Marsbäcken lies at 1 m above sea level. The nearest city is Västervik, 5.3 km to the southeast. Beaches nearby: Breviksbadet (3.9 km), Sandviksbadet (10 km), Idösund (15 km). Among the landmarks around are Smalspårsjärnvägen Hultsfred–Västervik (5.8 km), Sankta Gertruds kyrka, Västervik (5.2 km) and Lofta Church (17.2 km).