Brenan is both a surname and a given name. Notable people with the name include:
Surname:
Gerald Brenan (1894 – 1987), British writer and Hispanist
James Brenan (1837 – 1907), Irish artist
John Brenan (politician) (1798 – 1868), Australian politician from New South Wales
John Brenan (physician) (1768?- 1830), Irish physician
John Patrick Micklethwait Brenan (1917 – 1985), British botanist
Joseph Brenan (1828 – 1857), Irish writer and nationalist
Michael John Brenan (1780 – 1847), Irish Roman Catholic priest and historian
Given name:
Brenan (author) (fl. 1756)
Brenan Espartinez, Filipino singer