Sir John Williams may refer to:
Sir John Williams, 1st Baronet, of the City of London (1840–1926), Welsh physician and founder of the National Library of Wales Sir John Williams (Surveyor of the Navy) (1700–1784), British shipbuilder and designer General Sir John William Collman Williams (1823–1911), Royal Marines officer Sir John Williams, 2nd Baronet, of Eltham (1653–1723) English politician and Member of Parliament Sir John Williams, 2nd Baronet, of Llangibby (1651–1704) Welsh politician and Member of Parliament Sir John Williams (died 1743) (1675–1743) English merchant, Member of Parliament, and Lord Mayor of London Sir John Bickerton Williams (1792–1855) English nonconformist author and lawyer Sir John Hay-Williams, 2nd Baronet (1794–1859) Welsh baronet and High Sheriff
See also
John Williams (disambiguation)