The Guinness family is an extensive Irish family known for its accomplishments in brewing, banking, politics, and religious ministry. The brewing branch is particularly well known among the general public for producing the dry stout Guinness Beer. The founder of the dynasty, Arthur Guinness, is confirmed to have had McCartan origins. Beginning in the late 18th century, they became a part of what is known in Ireland as the Protestant Ascendancy. Four members of the family in succession held the UK Parliament constituency of Southend, which became popularly known as "Guinness-on-Sea". The "banking line" Guinnesses all descend from Arthur's brother Samuel (1727–1795) who set up as a goldbeater in Dublin in 1750; his son Richard (1755–1830), a Dublin barrister; and Richard's son Robert Rundell Guinness who founded Guinness Mahon in 1836.

Prominent members