William Markham may refer to:

• William Markham (MP) (by 1533–1571), MP for Nottingham (UK Parliament constituency)
• William Markham (bishop) (1710–1807), English scholar and religious figure
• William Markham (Governor) (1635–1704), first acting governor of colonial Pennsylvania
• William Markham (mayor) (1811–1890), Atlanta businessman and mayor
• William H. Markham (1888–1958), Wisconsin politician
• William Orlando Markham (1818–1891), English physician and pioneer of cardiology

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