William Herbert may refer to:

• William Herbert, 1st Earl of Pembroke (died 1469) (c. 1423–1469)
• William Herbert, 2nd Earl of Pembroke (1451–1491)
• William Herbert, 1st Earl of Pembroke (died 1570) (c. 1501–1570), Tudor period noble and courtier
• William Herbert, 3rd Earl of Pembroke (1580–1630)
• William Herbert, 6th Earl of Pembroke (c. 1640–1674), English nobleman and politician
• William Herbert, 18th Earl of Pembroke (born 1978)

• William Herbert, 1st Baron Powis (1572–1655), an English peer and landowner
• William Herbert, 1st Marquess of Powis (1626–1696), an English peer and landowner
• William Herbert, 2nd Marquess of Powis (1665–1745), an English and later British peer and landowner
• William Herbert, 3rd Marquess of Powis (1698–1748), a British peer and landowner

• William Herbert (MP fl.1555), MP for Monmouthshire 1555
• William Herbert (Captain), MP for Cardiff 1555
• Sir William Herbert (planter) (died 1593), Elizabethan planter in Ireland and MP for Monmouthshire 1584–1597
• William Herbert (died 1645), Welsh politician, MP for Cardiff 1621
• William Herbert (Royalist) (died 1642), Welsh politician, MP for Cardiff 1640
• William Herbert (died 1646) (1621–1646), English politician, MP for Monmouthshire 1640
• William Herbert (of Coldbrook) (died 1646), Welsh politician, MP for Monmouthshire 1626
• William Herbert (British Army officer) (c. 1696–1757), general and Member of Parliament
• William Herbert (antiquarian) (1771–1851), English librarian and antiquary
• William Herbert (bibliographer) (1718–1795), editor of Typographical Antiquities by Joseph Ames
• William Herbert (botanist) (1778–1847), British botanist, poet, and clergyman
• William Herbert Bradburn, Canadian politician
• William Norman Herbert (1880–1949), British general

• Herbert (surname)