John Stewart Miller (September 17, 1844 – April 25, 1936) was an Ontario farmer, merchant and political figure.
He represented Addington in the Legislative Assembly of Ontario as a Conservative member from 1886 to 1890.
He was born in Camden Township, Addington County, Canada West in 1844, the son of Thomas Miller and Christina Madden.
In 1870, he started a cheese factory in Centreville with James N. Lapum.
In 1883, Miller became a merchant in Centreville, purchasing the business of A. N. Lapum.