William Ahern

William or Liam or Bill Ahern may refer to:
 * Bill Ahern (footballer, born 1865) (1865–1938), Australian rules footballer for Carlton
 * Bill Ahern (footballer, born 1874) (1874–1920), Australian rules footballer for St Kilda
 * Liam Ahern (1916–1974), also known as William Ahern, Irish Fianna Fáil politician
 * William Ahern (Medal of Honor) (1861–1916), Irish-born American sailor
 * Will Ahern (1896–1983), American vaudeville entertainer