Gallagher may refer to:

• The surname Gallagher
• The American stand-up comedian known as Gallagher
• The New Zealand inventor of the electric fence, Alfred 'Bill' Gallagher
• Literary critic Catherine Gallagher
• The American actor David Gallagher
• U.S. comedian, actor and writer Jack Gallagher
• Canadian geologist John Gallagher
• Cartoonist John Gallagher
• Chessmaster Joseph Gallagher
• The British musicians Noel Gallagher and Liam Gallagher, members of the band Oasis
• The American actor Peter Gallagher
• The Irish guitarist Rory Gallagher
• British author and screenwriter Stephen Gallagher
• American artist Fred Gallagher, best known as the creator of Megatokyo.

Places in the United States:

• Gallagher Township, Pennsylvania
• The City of Gallagher, West Virginia

See also:

• The American electrical engineer Robert G. Gallager