James Brennan may refer to:

Politicians[edit]

• James F. Brennan (born 1952), American politician in the New York State Assembly
• James B. Brennan (1926–2021), American politician the Wisconsin State Senate
• James F. Brennan (mayor) (1916–2002), American politician, mayor of Somerville, Massachusetts
• James Brennan (Queensland politician) (1837–1917), Australian politician, member of the Queensland Legislative Assembly

Sports[edit]

• Don Brennan (baseball) (James Donald Brennan, 1903–1953), American Major League Baseball pitcher
• Jim Brennan (baseball) (1862–1914), American baseball player
• Jim Brennan (Australian footballer) (1927–2013), Australian rules footballer
• Jim Brennan (born 1977), Canadian soccer player and manager, also known as Jimmy Brennan
• Jim Brennan (Northern Irish footballer) (1932–2009), Northern Irish footballer
• James Brennan (footballer) (1884–1917), Irish footballer
• Jamie Brennan (born c. 1996/7), Irish Gaelic footballer
• Séamus Ó Braonáin (Jimmy Brennan, 1881–1970), Irish sportsman and public figure

Others[edit]

• James Herbert Brennan (born 1940), Northern Irish lecturer and author
• James Alexander Brennan (1885–1956), American songwriter
• James Brennan, a character in the film Adventureland