William Lithgow may refer to:
- William Lithgow (traveller and author) (1582–1645), Scottish traveller and author
- William Lithgow (judge) (1715–1798), judge for the Court of Common Pleas of Massachusetts
- William Lithgow (Auditor General of New South Wales) (b.1784), Scottish clergyman, first Auditor General of New South Wales
- William Lithgow (shipbuilder) (1854–1908), Scottish shipbuilder
- Sir William Lithgow, 2nd Baronet (born 1934), Scottish industrialist from shipbuilding family