Saint Martin is one of the twelve parishes of Jersey in the Channel Islands. It is 5.5 kilometres (3.4 mi) north-east of St Helier.

St Martin is the only parish in Jersey not to conduct its municipal business from a Parish Hall. St Martin has a Public Hall instead, having accepted money from the States of Jersey to provide an assembly room.

The village of Gorey is partly located in the parish, with the remainder of the village in Grouville. The village of Maufant is also partly located in St Martin, along the boundary with St Saviour.

The 600m breakwater at St. Catherine is all that remains of a grandiose harbour project started, but then abandoned, by the British government in the 19th century. It is now a popular site for sea anglers.

This is one of the most agricultural parishes, and one of the most sought after places to live in the island. It has the best herd of Jersey cattle, some of the largest potato growers and a number of small farmers now cultivating the new "Genuine Jersey", mainly organic, brand.

The main settlements in the parish are the villages of St Martin, Maufant and Gorey. Gorey is split with Grouville. The southern half of Maufant is located within St Martin, however the main road through the village is in St Saviour.

Mont Orgeuil is one of the two main castles in Jersey. First known as Gorey Castle and located near Gorey Pier, it has existed for 800 years. The castle was subject to raids by the French in the 13th, 14th and 15th centuries. The castle served as the island's prison until a prison was constructed in St. Helier in the 17th century. Among agitators imprisoned there by the British government were William Prynne and John Lilburne. Until the construction of Elizabeth Castle off St. Helier at the beginning of the 17th century, Mont Orgueil was generally the residence of the Governor of Jersey.