Arthur Guinness (c. 24 September 1725 – 23 January 1803) was an Irish brewer, entrepreneur, and philanthropist who founded the Guinness Brewery at St. James's Gate in Dublin in 1759. He originally started as a brewer of ale but began producing porter (a dark beer) in 1778, which became highly popular, leading him to stop brewing ale by 1799. Arthur Guinness famously signed a 9,000-year lease for the brewery site at St. James's Gate, and his beer brand grew to become globally recognized. Besides his brewing career, he was socially active, founded the first Sunday school in Dublin, and supported Catholic rights though he opposed the Irish Rebellion of 1798. He had ten children, and his brewery was passed down to his son after his death in 1803. His legacy includes the creation of one of the world's most famous beers and a lasting family business empire.

Additionally, there is a later Arthur Guinness (Arthur Edward Guinness, 1st Baron Ardilaun, 1840–1915), a notable descendant who also played a significant role in the brewery’s history and public life, but the original founder was the 18th-century Arthur Guinness.