Cornelius Newton Bliss (January 26, 1833 - ?) was an American merchant and politician.

Cornelius Bliss was born at Fall River, Massachusetts. He was educated in his native city and in New Orleans, where he early entered his stepfather's counting-house. Returning to Massachusetts in 1849, he became a clerk and subsequently a junior partner in a prominent Boston commercial house. Later he moved to New York City to establish a branch of the firm. In 1881, he organized and became president of Bliss, Fabyan & Company, one of the largest wholesale dry-goods houses in the country. A consistent advocate of the protective tariff, he was one of the organizers and for many years president of the American Protective Tariff League . In politics an active Republican, he was chairman of the Republican state committee in 1887 and 1888, and contributed much to the success of the Harrison ticket in New York in the latter year. He was treasurer of the Republican National Committee from 1892 to 1904, and was United States Secretary of the Interior in President William McKinley's cabinet from 1897 to 1899.