She was born in St. Louis, Mo., the daughter of Joseph M. Field, was educated in New England and in England, and prolonged her stay in Europe as correspondent of various American newspapers, writing also for magazines. On her return she gave lectures and public readings and in 1874 appeared as Peg Woffington at Booth's Theatre, New York. She afterward abandoned the regular comedy for dance, song, and recitation, but achieved no striking success. In 1882-83 she headed a Coöperative Dress Association in New York, which achieved a conspicuous failure. In 1889 she established Kate Field's Washington, a weekly journal published in the capital. After 1868 she published numerous volumes of miscellaneous contents, no longer noteworthy.

Kate Field never married. In October 1860, while visiting his mother's home in Florence, Italy, the celebrated British novelist Anthony Trollope met Kate. She became one of his closest friends and was the subject of Trollope's high esteem, as noted in his "Autobiography": "There is an American woman, of whom not to speak in a work purporting to [be] a memoir of my own life would be to omit all allusion to one of the chief pleasures which has graced my later years." Trollope scholars have speculated on the nature of their warm friendship. Twenty-four of his letters to Kate survive, at the Boston Public Library; hers to Trollope do not.

Kate Field died of pneumonia in 1896.