Percy Daniels (September 17, 1840 in Globe Village in Woonsocket, Rhode Island – February 14, 1916 in Girard, Kansas) was an American soldier, businessman, civil engineer, surveyor, author and Populist politician.

He also acquired land in Crawford Township near Girard which he named "Narragansett Farm" in memory of his native Rhode Island.

In 1890 he purchased the Girard Herald newspaper in order to advance his views, such as that the Republican party should "destroy the trusts" and institute better methods of taxation, such as a graduated estate tax.

Daniels' political career largely ended with the swift decline of the People's Party after the national election of 1896.

These included A Lesson of Today and a Question of To-morrow (1892), A Sunflower Tangle Over Problems of Taxation (1894), Cutting the Gordian Knot (1896), The Midnight Message of Paul Revere (1896), Man Versus Mammon (1897), Swollen Fortunes and the Problem of the Unemployed (1908), and Graduated Property Taxation (1911).

Daniels and his wife Eliza Eddy had five children: Frank Leonard (1869–70), Frederic Percy (1871-1950), Walter Horton (1873-1950), Elizabeth Buttrick (1877-1965), and Earle Newton (1880-1970).