The Eutin–Neustadt railway was a 16-kilometer-long, non-electrified branch line, running from Eutin to Neustadt in Holstein in the German state of Schleswig-Holstein.

Neustadt in Holstein is a town in the district of Ostholstein, in Schleswig-Holstein, Germany, on the Bay of Lübeck 30 km northeast of Lübeck, and 50 km southeast of Kiel.