St John is one of the twelve parishes of Jersey and is around 7.3 kilometres (4.5 mi) north of St Helier on the north coast of the island. St John's Village is also the name of the main village in the parish.

The parish is largely rural, with two main settlements: its namesake village and the village of Sion on the border with St Helier.

The church is dedicated to St John the Baptist and the symbol for St John has links to the Crusades - the Maltese cross is used within Jersey to depict the Parish of St John. The full name of the church is Saint-Jean des Chênes (St John of the Oaks). The church is known to have existed as early as 1150.

The Jersey parish system has been in place for centuries. By Norman times, the parish boundaries were firmly fixed and remain largely unchanged since.

In 1180 Jersey was divided by the Normans into three ministeria for administrative purposes. St John was part of de Groceio. De Groceio likely refers to the Jersey family name, de Gruchy.

La Route du Nord was constructed during the German occupation of the Channel Islands as a scheme to provide work. The road is now dedicated to the men and women of Jersey who suffered 1939-1945.

Largely a rural community, the namwsake has a small shopping precinct, and village pub, around its parish church, with the primary school and parish hall across the main road. There is also a supermarket and recreation centre to the east of the village.

There is also a second village of Sion in the Southwestern panhandle of the parish. This is quite a small village centred around the main road. It has a small shop and a garage.

The cliffs of the north coast afford some of the best views in Jersey. After Trinity, it has the second highest point in Jersey at Mont Mado (473 ft). The parish covers territory of 4,846 vergées.

There is a single usable beach in the parish at the Bonne Nuit harbour, accessible by a hilly windy road that connects to the village.

Mont Mado granite was quarried historically. The largest quarry is now that of Ronez on the north coast.