Boag is a surname. Notable people with the surname include:
Carly Boag (born 1991), Australian basketball player; Colin Boag, British Army officer; Erin Boag (born 1975), New Zealand ballroom dancer; G. T. Boag (1884–1969), British civil servant; James Boag I (c. 1804–1890), Australian brewery founder and proprietor; James Boag II (1854–1919), Australian brewery proprietor; John Boag (disambiguation), various people; Keith Boag, Canadian television journalist; Michelle Boag (born 1954), New Zealand public relations practitioner; Peter Boag, Canadian scientist; Stuart Boag (disambiguation), various people; Tommy Boag (1814–1977), Australian rules footballer; Wally Boag (1920–2011), American stage performer; Yvonne Boag (born 1954), Scottish-born Australian artist.
See also Boag's Brewery, an Australian brewery