Eupatorium mohrii, commonly called Mohr's thoroughwort, is a herbaceous perennial plant in Asteraceae native to the southeastern and south-central states of the United States, in the coastal plain from Virginia to Texas. It has also been found in the Dominican Republic. Eupatorium mohrii is a perennial herb up to 100 cm (40 inches) tall and are producing tuberous rhizomes. As with other species of Eupatorium, the inflorescences contain a large number of tiny white flower heads, each with 5 disc florets but no ray florets. It forms hybrids with Eupatorium serotinum and Eupatorium rotundifolium.