Segeberg (German pronunciation: [ˈzeːɡəˌbɛʁk] ⓘ; North Frisian: Segebärj) is a district in Schleswig-Holstein, Germany.

It is bounded by (from the southwest and clockwise) the districts of Pinneberg, Steinburg and Rendsburg-Eckernförde, the city of Neumünster, the districts of Plön, Ostholstein and Stormarn, and the city state of Hamburg.

The district of Segeberg consists of the agricultural plains between the cities of Neumünster and Hamburg.

A southwestern portion of the hilly lakeland called "Holsteinische Schweiz" (Holsatian Switzerland) belongs to the district, as well as some northern suburbs of Hamburg.

The coat of arms displays: Media related to Kreis Segeberg at Wikimedia Commons