William Glen or Glenn may refer to:
William Glen (geologist) (1932–2025), American geologist and historian of science William Glen (poet) (1789–1826), Scottish poet William Glen (footballer) (1903–1981), Irish football player William Glenn (1914–2003), American cardiac surgeon William E. Glenn (1926–2013), American inventor William H. Glenn (1872–1940), American industrialist Billy Glenn (William Spiers Glenn, 1877–1953), New Zealand politician