Preseli Pembrokeshire (Welsh: Preseli Sir Benfro) is a seat and constituency of the House of Commons of the Parliament of the United Kingdom.^{[n 1]}

The Preseli Pembrokeshire Senedd constituency was created with the same boundaries in 1999.

Its MP, who has held the seat since 2005, is the Conservative Stephen Crabb, who was Secretary of State for Work and Pensions (Work and Pensions Secretary) from March to July 2016. The seat was held by Labour's candidate from its creation in 1997 until 2005. The Labour and Conservative parties have won at least 27.7% of the vote apiece since its 1997 creation, with the next-placed parties having reached a maximum of 14.5% of the vote to date in a generally broad field.

The seat attracted five candidates in 2010, eight in 2015 (an election in which five of the deposits were refunded and three lost) and seven in 2017. At the 2017 election, Crabb's majority was the 27th closest out of the 650 Commons seats, 0.8% or 314 votes.^[2] In 2019, there were four candidates; Crabb retained the seat with an increased majority.

The constituency is set to be abolished, as part of the 2023 Periodic Review of Westminster constituencies and under the June 2023 final recommendations of the Boundary Commission for Wales for the next United Kingdom general election. Its wards is to be split between Ceredigion Preseli, and Mid and South Pembrokeshire.^[3]

The seat is predominantly rural with both Welsh and English speaking areas. Milford Haven has a significant port and oil industry, and tourism is also a key sector due to the Pembrokeshire Coast National Park.^[4] The seat is less affluent than the UK average.^[5]

The constituency was created in 1997 from parts of the seats of Ceredigion and Pembroke North and Pembroke. It comprises the north and west coasts of Pembrokeshire and areas inland, including the Preseli Hills in the north of the county. It is the most westerly constituency in Wales. Much of the coastal area is in the Pembrokeshire Coast National Park.

On its creation in 1997, its boundaries were co-terminous with the then District of Preseli Pembrokeshire. Since the 2006 boundary review of Welsh parliamentary constituencies, which took effect at the 2010 general election, it consists of the Pembrokeshire County electoral divisions of: Burton; Camrose; Cilgerran; Clydau; Crymych; Dinas Cross; Fishguard North East; Fishguard North West; Goodwick; Haverfordwest Castle; Haverfordwest Garth; Haverfordwest Portfield; Haverfordwest Prendergast; Haverfordwest Priory; Johnston; Letterston; Llangwm; Llanrhian; Maenclochog; Merlin's Bridge; Milford Central; Milford East; Milford Hakin; Milford Hubberston; Milford North; Milford West; Newport; Neyland East; Neyland West; Rudbaxton; St David's; St Dogmaels; St Ishmael's; Scleddau; Solva; The Havens; and Wiston.

• Preseli Pembrokeshire (Senedd constituency)
• List of parliamentary constituencies in Dyfed
• List of parliamentary constituencies in Wales