Alleyn is a surname. Notable people with the surname include:
Charles Joseph Alleyn (1817-1890), Quebec lawyer and political figureEdward Alleyn (1566-1626), English actorJames Alleyn (1683-1746), English educationalistSir John Alleyne, 1st Baronet (1724–1801), Speaker of the House of Assembly of BarbadosSir John Alleyne, 3rd Baronet (1820–1912), British businessman and engineerJohn Alleyn (surgeon) (died 1686), surgeon and fifth Master of the College of God's Gift in DulwichJohn Alleyn (MP) (1621-1663), British barrister and MP for Mitchell (Michael)Matthias Alleyn (died 1642), second Master of the College of God's Gift in DulwichRaph Alleyn (died c. 1677), fourth Master of the College of God's Gift in DulwichRoderick Alleyn, a fictional police detectiveThomas Alleyn (3rd Master of Dulwich College) (died c. 1668), third Master of the College of God's Gift in DulwichThomas Alleyn (Barber-Surgeon) (died 1631), first Master of the College of God's Gift in Dulwich