Isaac Ambrose Barber (January 26, 1852 – March 1, 1909) was a U.S. Representative from Maryland, serving from 1897 to 1899.

Born near Salem, New Jersey, Barber attended the common schools and studied medicine in Hahnemann Medical College of Philadelphia, from which he was graduated in 1872.

[1] Barber served as a member of the Maryland House of Delegates in 1895, and later as president of the Farmers & Merchants' National Bank of Easton.

[1] After Congress, he resumed the milling business and also engaged in agricultural pursuits.

Barber died at his home in Easton on March 1, 1909, and is interred in Spring Hill Cemetery.