Hardin is a surname. Notable people with the surname include:
- Charles Hardin Holley (1936-1959), birth name of Buddy Holly
- Charles Henry Hardin (1820–1892), co-founder of Beta Theta Pi fraternity
- Chelsea Hardin, American beauty pageant titleholder, Miss Hawaii USA 2016, and 1st runner up Miss USA 2016
- Clifford M. Hardin, U.S. Secretary of Agriculture
- DeVon Hardin, American basketball player
- Garrett Hardin (1915–2003), American ecologist
- George A. Hardin (1832–1901), New York lawyer and politician
- Glen Hardin, American musician/piano player
- Glenn Hardin (1910–1975), American athlete
- Jerry Hardin, American actor
- Jim Hardin (1943–1991), American baseball player
- Jo Hardin, American statistician
- John Hardin (1753–1792), Continental Army officer in the American Revolutionary War
- John J. Hardin (1810–1847), U.S. Representative from Illinois
- John Wesley Hardin (1853–1895), outlaw and gunfighter of the American Old West
- Joseph Hardin Sr. (1734-1801), Patriot in the American Revolutionary War and politician.
- Julia Hardin, All-American Girls Professional Baseball League player
- Lil Hardin Armstrong (1898–1971), American jazz musician and second wife of Louis Armstrong
- Louis T. Hardin (1916–1999), American musician known as Moondog
- Martin Davis Hardin (1837–1923), Union Army general in the American Civil War
- Martin D. Hardin (1780–1823), U.S. Senator from Kentucky
- Melora Hardin, American actress
- Paul Hardin Jr. (1903–1996), bishop of The Methodist Church (USA)
- Rusty Hardin, American attorney
- Salvor Hardin, fictional character in Isaac Asimov's Foundation series
- Terri Hardin, American puppeteer
- Tim Hardin (1941–1980), American folk musician and composer
- Ty Hardin (1930-2017), American actor