Thurrock (/ˈθʌrək/) is a unitary authority area with borough status in the ceremonial county of Essex, England. It lies on the north bank of the River Thames immediately east of London and has over 18 miles (29 km) of riverfront including the Port of Tilbury, the principal port for London. Thurrock is within the London commuter belt and is an area of regeneration within the Thames Gateway redevelopment zone. The borough includes the northern ends of the Dartford Crossing.

The local authority is Thurrock Council, based in Grays. The borough also includes Purfleet-on-Thames, South Ockendon, Stanford-le-Hope and Tilbury, as well as other villages and surrounding areas. More than half of the borough is designated as Green Belt.

The neighbouring districts are the London Borough of Havering, Brentwood, Basildon and Castle Point. On the opposite side of the Thames are Gravesham and Dartford in Kent.

Mammoths once grazed in the Thurrock area and archaeologists unearthed the remains of a jungle cat. Humans have lived in the area since prehistoric times and the land has been farmed by the Romans and Anglo-Saxons. Thurrock has numerous archaeological sites including the major excavation at Mucking. The name "Thurrock" is a Saxon name meaning "the bottom of a ship".

Horndon-on-the-Hill was the site of an 11th century mint as well as the 15th century woolmarket which gives an indication of the area's wealth in the 15th century. The narrowing of the river where Tilbury now stands meant it was important in the defence of London, and Henry VIII built three blockhouses, two on the Tilbury side and another on the Gravesend side of the river, following the end of his marriage to Catherine of Aragon.

In 1381, villagers from Fobbing, Mucking and Stanford-le-Hope instigated the Peasants' Revolt when they were called to Brentwood to pay the poll tax. When they refused to pay, a riot ensued which was the catalyst for a mass protest across Essex and Kent.

Later, in 1588 Elizabeth I addressed her troops not far from the Tilbury blockhouse as the Spanish Armada sailed up the English Channel. Between 1670 and 1682, the Tilbury blockhouse was substantially rebuilt into a much larger fortification (Tilbury Fort) and Coalhouse Fort was built further down river, close to the second blockhouse. The importance of the forts in defending the country continued through Napoleonic times and into the two world wars. The land where Tilbury Town now stands was farmland and marsh grazing until the building of the docks in the 1890s. Thurrock includes the Bata village, built for workers of the shoe company in 1933. Eight homes and the factory are listed.

Historically, the area was renowned for mineral extraction, including clay, aggregates and notably the digging of huge amounts of chalk from the West Thurrock area for use in the now defunct cement industries. When chalk extraction ceased one of the disused pits was redeveloped as Lakeside Shopping Centre. A number of former pits have been used to form the Chafford Gorges Nature Reserve, managed by the Essex Wildlife Trust.