Gallacher is a surname of Scottish origin and is a variant of the Gaelic Ó Gallchóbhair found chiefly in Scotland. The name Ó Gallchóbhair has been variously anglicised as Gallagher, Gallaher, Gallaugher, Goligher etc.

Notable people with the surname include:

• Brian Gallacher, Scottish footballer
• Bernard Gallacher, Scottish golfer
• Frank Gallacher, Scottish-Australian actor
• Hughie Gallacher, Scottish international footballer (Airdrieonians, Newcastle United)
• Jim Gallacher, Scottish football goalkeeper (Clydebank)
• Kevin Gallacher, Scottish football player and TV sports pundit
• Kirsty Gallacher, Scottish television presenter often specialising in sport programmes
• Liz Gallacher, British film music supervisor
• Mike Gallacher, Australian politician
• Pat Gallacher, Scottish footballer (Partick Thistle, Tottenham Hotspur, Luton Town)
• Pat Gallacher (footballer, born 1913) (1913–1983), Scottish footballer
• Patrick Gallacher,"Patsy", Scottish international footballer (Sunderland, Stoke City, Scotland)
• Patsy Gallacher, Irish footballer (Celtic)
• Paul Gallacher, Scottish international football goalkeeper (Dundee United, Norwich City, Dunfermline Athletic, St Mirren, Partick Thistle)
• Skeets Gallacher (1925–2013), Scottish boxer
• Stephen Gallacher, Scottish golfer
• Stirling Gallacher, English TV and stage actress
• Tom Gallacher, Scottish playwright
• Tommy Gallacher (1922–2001), Scottish footballer (Dundee)
• Willie Gallacher, Scottish trade unionist, activist and communist