Alexander Forbes may refer to:

• Alexander Forbes, 1st Lord Forbes (died 1448), Scottish baron
• Alexander Forbes, 4th Lord Forbes (died 1491), Scottish baron
• Alexander Forbes, 10th Lord Forbes (died 1672), Scottish baron, the 10th Lord Forbes
• Alexander Forbes, 4th Lord Forbes of Pitsligo (1678–1762), Scottish philosopher and Jacobite

• Alexander Forbes (bishop of Aberdeen) (1564–1617), bishop of Aberdeen
• Alexander Forbes (bishop of Brechin) (1817–1875), Scottish Episcopal Bishop of Brechin
• Alexander Kinloch Forbes (1821–1865), British administrator in India, writer
• Alexander Forbes (explorer) (1778–1862), Scottish explorer
• Alexander F. I. Forbes (1871–1959), South African astronomer
• Alexander Forbes (neurophysiologist) (1882–1965), American neurophysiologist and medical school professor
• Alex Forbes (1925–2014), Scottish football player (Arsenal, Scotland)
• Alex S. Forbes (fl. 1928–1935), Scottish football player
• Jim Forbes (Australian politician) (Alexander James Forbes, 1923–2019), Australian soldier and politician

• Alexander Forbes Group Holdings, a financial services group with its head office in South Africa