Grube is a municipality in the district of Ostholstein, in Schleswig-Holstein, Germany. It is situated near the Baltic Sea coast, approx. 15km south of Heiligenhafen, and 45km northeast of Lübeck.
Grube was the seat of the Amt ("collective municipality") Grube, which was disbanded in January 2007. It consisted of the following municipalities (population in 2005 between brackets):