Napoleon Bonaparte Thistlewood (March 30, 1837 – September 15, 1915) was a veteran of the American Civil War who served as a U.S. Representative from the state of Illinois from 1908 to 1913.

Napoleon Thistlewood was born in Kent County, Delaware, near the town of Harrington.

Thistlewood enlisted in the Union Army in 1862 and served as captain of Company C, Ninety-eighth Regiment, Illinois Volunteer Infantry.

At the conclusion of his second mayoral term in Cairo, Thistlewood was named Department Commander of the Grand Army of the Republic for Illinois (1901).

Thistlewood was elected as a Republican to the Sixtieth Congress to fill the vacancy caused by the 1907 death of George W. Smith.