Sure, here are the eight U.S. Presidents who died while in office:
1. **William Henry Harrison** (1841) - Died of pneumonia just a month after taking office.
2. **Zachary Taylor** (1850) - Died of illness, likely acute gastroenteritis.
3. **Abraham Lincoln** (1865) - Assassinated by John Wilkes Booth.
4. **James A. Garfield** (1881) - Assassinated by Charles J. Guiteau.
5. **William McKinley** (1901) - Assassinated by Leon Czolgosz.
6. **Warren G. Harding** (1923) - Died of a heart attack.
7. **Franklin D. Roosevelt** (1945) - Died of a cerebral hemorrhage.
8. **John F. Kennedy** (1963) - Assassinated by Lee Harvey Oswald.