Setmurthy is a civil parish in Allerdale, Cumbria, England, historically part of Cumberland, within the Lake District National Park in England. In the 2011 census it had a population of 110. The spelling "Satmurthawe" is seen in 1473.

The River Derwent forms the northern and eastern boundary of the parish, separating it from Blindcrake. Bassenthwaite Lake forms the eastern boundary, and the parish is then bordered by Above Derwent to the south east, Embleton to the west and south, and Cockermouth and Bridekirk to the west. The main settlement is the hamlet of Dubwath.

The parish church of St Barnabas, built in 1794, is grade II listed; it is in the Diocese of Carlisle and the Binsey Mission Community.

Watch Hill, also known as Setmurthy Common, reaches 254 metres (833 ft) and because of its relative isolation qualifies as a marilyn, a hill with 150 m of topographic prominence. Alfred Wainwright includes it in his The Outlying Fells of Lakeland, recommending an ascent from the west and a return on the same route. He comments that "It is easily attained with a minimum of effort: a stroll on grass so simple that boots are incongruous footwear for it and bare feet appropriate".

Setmurthy is within the Copeland UK Parliamentary constituency, Trudy Harrison is the Member of parliament.

Before Brexit, it was in the North West England European Parliamentary Constituency.

For Local Government purposes it is in the All Saints Ward of Allerdale Borough Council and the Bothel + Wharrels Division of Cumbria County Council.

There is a joint parish council with the parishes of Embleton and Wythop, known as Embleton and District Parish Council.

As of 2017 there are nine listed buildings in the parish; Hewthwaite Hall, dating from 1581, is grade II* and the others are grade II.

• Cumbria County History Trust: Setmurthy (nb: provisional research only – see Talk page)
• Setmurthy: historical and genealogical information at GENUKI.

54°41′N 3°16′W / 54.68°N 3.27°W / 54.68; -3.27