Tasdorf is a municipality located in the district of Plön within the German state of Schleswig-Holstein. It is situated on the northeastern city limits of Neumünster and covers a total municipal area of approximately 5 km². The current population of the village is about 360 people.
The settlement has a documented history dating back to at least 1141 AD. Geographically, the brook Dosenbek flows through the municipal area as it travels from the Dosenmoor nature reserve toward Neumünster. Additionally, the village is located south of a closed railroad line that formerly connected Neumünster and Ascheberg.