Commodore William Henry Alexander Macomb (June 16, 1818 – August 12, 1872) was an officer in the United States Navy who served during the American Civil War.
He married Mary Eliza Stanton (his sister's step-daughter) on 17 January 1844 in Fort Hamilton, New York.
Macomb served with distinction during the Civil War, being promoted to commander in 1862.
For his gallantry in action with the North Atlantic Squadron, he was promoted to captain in 1866, and finally to commodore in 1870.
He was elected as a companion of the Pennsylvania Commandery of the Military Order of the Loyal Legion of the United States (MOLLUS) on September 19, 1866.