William McLellan may refer to:
- William McLellan (Australian politician) (1831–1906), mining agent and politician in colonial Victoria
- William McLellan (Scottish electrical engineer) (1874–1934), known for contributions to hydroelectric power
- William McLellan (American electrical engineer) (1924–2011), known for contributions to nanotechnology
- William Walker McLellan (1873–1960), founder of McLellan Stores
- William H. McLellan (1832–1912), American lawyer and politician
See also
edit- William Maclellan (15th century), Scottish nobleman
- William E. McLellin (1806–1883), early leader in the Latter Day Saint movement