Ostróda County (Polish: powiat ostródzki) is a unit of territorial administration and local government (powiat) in Warmian-Masurian Voivodeship, northern Poland.

It came into being on January 1, 1999, as a result of the Polish local government reforms passed in 1998.

Its administrative seat and largest town is Ostróda, which lies 37 kilometres (23 mi) west of the regional capital Olsztyn.

The county covers an area of 1,764.89 square kilometres (681.4 sq mi).

The county is subdivided into nine gminas (one urban, three urban-rural and five rural).