Oldendorf (meaning: "old village") is a village and Ortschaft in the municipality of Südheide in the northern part of Celle district in Lower Saxony, Germany. It lies on the western edge of the Southern Heath Nature Park, on the Lüneburg Heath, about 2 km south of the main village of Hermannsburg and currently has about 640 inhabitants. In 1973 Oldendorf was incorporated into Hermannsburg as part of the Lower Saxony regional and administrative reforms.