Ostróda County (Polish: powiat ostródzki) is a unit of territorial administration and local government (powiat) in Warmian-Masurian Voivodeship, northern Poland. It was created on January 1, 1999 as a result of the Local Government Reorganization Act of 1998. Its administrative seat and largest town is Ostróda, which lies 37 kilometres (23 mi) west of the regional capital Olsztyn. The county contains three other towns: Morąg, 25 km (16 mi) north of Ostróda, Miłakowo, 34 km (21 mi) north of Ostróda, and Miłomłyn, 12 km (7 mi) north-west of Ostróda.
The county covers an area of 1,764.89 square kilometres (681.4 sq mi). As of 2006 its total population is 105,286, out of which the population of Ostróda is 33,419, that of Morąg is 14,497, that of Miłakowo is 2,665, that of Miłomłyn is 2,305, and the rural population is 52,400.
The county is subdivided into nine gminas (one urban, three urban-rural and five rural). These are listed in the following table, in descending order of population.