Adam Dietrich (November 4, 1711, in Ziegenhain; July 11, 1782, there) was a German botanist. Dietrich was a farmer and was likely instructed in herbalism by his father-in-law. He self-taught himself a wealth of botanical knowledge. In 1742, he personally met the botanist Albrecht von Haller and contributed to the preliminary studies for the new edition of Heinrich Bernhard Rupp's Flora Jenensis. The botanist Carl von Linné began a scientific exchange with Dietrich, which led other scholars to seek a connection with him as well. His extensive botanical knowledge is repeatedly referenced in the most important contemporary botanical journals. Dietrich was the grandfather of the botanist and landscape designer Johann Christian Gottlieb Dietrich.