Æthelberht, Aethelbert or Ethelbert is a masculine given name which may refer to:

• Æthelberht of Kent (c. 550–616), King of Kent
• Æthelred and Æthelberht (died c. 669), possibly legendary princes of Kent, saints and martyrs
• Æthelberht, king of the Hwicce (fl. 692–693)
• Æthelbert of Sussex (fl. 8th century), King of Sussex
• Alberht of East Anglia (8th century), also Æthelberht I of East Anglia, ruler of East Anglia
• Æthelbert II of Kent (725–762), King of Kent
• Æthelbert of York (died 780), Archbishop of York, scholar and teacher
• Æthelberht II of East Anglia (died 794), saint and King of East Anglia
• Æthelberht of Whithorn (died 797), Bishop of Whithorn
• Æthelberht, King of Wessex (died 865)

• Ethelbert Barksdale (1824–1893), American and Confederate politician
• Ethelbert Blatter (1877–1934), Swiss Jesuit priest and pioneering botanist in British India
• E. W. Bullinger (1837–1913), Anglican clergyman, biblical scholar and theologian
• Ethelbert Callahan (1829–1918), American lawyer and politician
• Ethelbert Nevin (1862–1901), American pianist and composer
• Ethelbert I. Singley (1888–1967), American politician
• Ethelbert Stauffer (1902–1979), German Protestant theologian and numismatist
• Ethelbert Talbot (1848–1928), 15th presiding bishop of the Episcopal Church
• Ethelbert Dudley Warfield (1861–1936), American professor of history and college president
• Ethelbert Watts (1846–1919), American diplomat in World War I
• Ethelbert White (1891–1972), English wood engraver and painter

• Ethelbert (orca), a whale that swam up the Columbia River