John Adam Eckfeldt (June 15, 1769 – February 6, 1852; usually Adam Eckfeldt) was a worker and official in the early days of the United States Mint. A lifelong Philadelphian, Eckfeldt served as the second chief coiner of the Mint, from 1814 until 1839.
Eckfeldt's father owned a large smithy and involved himself in early attempts at American coinage. Adam Eckfeldt built early presses for the Mint, engraved some of its early dies, and was responsible for the designs of early American copper coinage, as well as the 1792 half disme which some authorities consider the first United States coin. He was appointed assistant coiner of the Mint in 1796, and became chief coiner on his predecessor's death in 1814.