Wyszków County (Polish: powiat wyszkowski) is a unit of territorial administration and local government (powiat) in Masovian Voivodeship, east-central Poland. It originally existed from 1956 until the abolition of the powiats in 1975, but was re-created on January 1, 1999, as a result of the Polish local government reforms passed in 1998, which reintroduced the powiats and created 16 large voivodeships. The administrative seat and only town in the county is Wyszków, which lies 53 kilometres (33 mi) north-east of Warsaw.

The county covers an area of 876.49 square kilometres (338.4 sq mi). As of 2006 its total population is 71,558, out of which the population of Wyszków is 27,010 and the rural population is 44,548.

Wyszków County is bordered by Ostrołęka County to the north, Ostrów Mazowiecka County to the north-east, Węgrów County to the east, Wołomin County to the south, Legionowo County and Pułtusk County to the west, and Maków County to the north-west.

The county is subdivided into six gminas (one urban-rural and five rural). These are listed in the following table, in descending order of population.

Wyszków [ˈvɨʂkuf] is a town in northeastern Poland with 26,500 inhabitants (2003). It is the capital of Wyszków County (Polish: powiat wyszkowski). Wyszków is in the Masovian Voivodeship (since 1999); previously it was in the Warsaw Voivodeship (until 1975) and the Ostrołęka Voivodeship (1975–1998).

The village of Wyszków was first documented in 1203. The town was founded in 1502. It was destroyed during the Second Northern War in 1655-1660, when it lost its significance in the region. Industry developed after 1897, when the Pilawa-Tluszcz-Ostrołęka railway was built.

Before World War II half of Wyszków's population of 9,000 were Jewish; after the war there were none. On 14 September 1997 a memorial to Holocaust victims was unveiled in Wyszków. It is made of reclaimed Jewish gravestones that had been removed from the site in 1939 by German forces, who used them as paving stones and to build the local Gestapo headquarters. Scores of these desecrated tombstones were recovered and incorporated as part of the monument.