Ashbel Green Simonton (January 20, 1833-December 9, 1867) was a Presbyterian minister and missionary.
Simonton was ordained by the Presbyterian Church in the United States of America in April 14, 1859. In November, 1858, he proposed for missionary work and in June 18, 1859 went for Brazil, arriving at August 12, 1859. In Brazil he planted the Presbyterian Church of Brazil (Igreja Presbiteriana do Brasil), in January 12, 1862.