Brannan is a surname. Notable people with the surname include:
Real people Andy Brannan (1919–1997), Australian rules footballer Andrew Brannan (1948–2015), American Vietnam war veteran and criminal Charles F. Brannan (1903–1992), United States Secretary of Agriculture, 1948–1953 John Brannan (1819–1892), American officer who served in the Civil War and Mexican–American War Justin Brannan, New York City politician and retired punk rock musician Mike Brannan (1955–2013), American golfer Samuel Brannan (1819–1889), American businessman and journalist Samuel S. Brannan (1835–1880), American politician and newspaper editor Solomon Brannan (born 1942), American football player Thomas Brannan (1893–1960), English rugby league footballer who played in the 1910s and 1920s
Fictional characters Josh Brannan, character in the NBC series Last Resort