| Isaiah Dunn Clawson | |
| State: | New Jersey |
| District: | 1st |
| Party: | Opposition Party (1st term) Republican (2nd term) |
| Term: | March 4, 1855 - March 3, 1859 |
| Preceded: | Nathan T. Stratton |
| Succeeded: | John T. Nixon |
| Birth Date: | March 30, 1822 |
| Birth Place: | Woodstown, New Jersey |
| Death Place: | Woodstown, New Jersey |
| Profession: | Physician, Politician |
Isaiah Dunn Clawson (March 30, 1822 – October 9, 1879) was an American Opposition Party / Republican Party politician who represented New Jersey's 1st congressional district in the United States House of Representatives from 1855 to 1859.
Born in Woodstown, New Jersey, on March 30, 1822, Clawson attended Delaware College, (Newark, Delaware) and Lafayette College Easton, Pennsylvania, and graduated from Princeton College in 1840 and from the University of Pennsylvania School of Medicine in 1843. He commenced the practice of medicine in Woodstown. He served as a member of the New Jersey General Assembly in 1854.
He was elected as an Opposition Party candidate to the Thirty-fourth Congress and reelected as a Republican to the Thirty-fifth Congress, serving in office from March 4, 1855, to March 3, 1859, but was not a candidate for renomination in 1858.
After leaving Congress, he resumed the practice of medicine in Woodstown, where he died on October 9, 1879. Interment in the Baptist Cemetery.