Cyrus Bryant (12 July 1798 – 19 February 1865)[1] was an American educator and scientist and member of Academy of Natural Sciences in Philadelphia.

Cyrus was born in Cummington, Massachusetts in a family of Peter Bryant (1767–1820), a doctor and later a state legislator, and Sarah Snell.

After returning to Cummington, Cyrus helped organize the local lyceum and spent a few years teaching chemistry and mineralogy.

In 1832, together with his brother Arthur, Cyrus moved to Princeton, Illinois, where in 1834 married Julia Everett (1808–1875).

In Princeton, he resumed his past activities and served as county clerk and a teacher of chemistry and botany.