Horndon on the Hill is a village and Church of England parish in the unitary authority of Thurrock, in the county of Essex, England. It is located close to the A13 road, around one mile northwest of Stanford-le-Hope and around two miles northeast of Orsett.
Horndon-on-the-Hill has one church, the Church of St Peter and St Paul, which dates from the 13th century and is Grade I listed.
The parish was part of the Orsett Rural District from 1894 until 1936 and the Thurrock Urban District from 1936 until 1974. Since 1974 it has been located in the Thurrock District in Essex (a unitary authority since 1998).