【Background】Invasive organisms have to adapt to the stresses in their new enviornments. This can include adaptation to heat stress, known to occur in plants. There is evidence that such adaptation to heat stress is related to various physiological metabolisms. 【Method】Ultrastrutural cytochemical localization of ATPase activity of heatresistant and susceptible populations of Eupatorium adenophorum （Spreng.） was investigated to explore the role of ATPase activity and distribution in the cell. 【Result】The ATPase of E.adenophorum naturally was located at the cell wall and the surface of cell wall bordering the intercellular spaces. ATPase activity in resistant vs.susceptible populations at 40 ℃ high temperature had significant difference and was recorded 12 hours after heat treatment was applied. ATPase of the resistant populations remained active on many localized sites, including the cell wall and plasma membranes, whereas ATPase activity of susceptible populations obviously decreased, with only sporadic activity spots remaining on the cell wall. Twentyfour hours later, the leaves of susceptible populations completely wilted whereas some dots of ATPase were found on plasma membranes of resistant populations and the chloroplast ultrastructure was only slightly damaged. 【Conclusion and significance】After treatment at 40 ℃, high temperature resistant populations of E.adenophorum ATPase activity was less damaged than in the temperaturesusceptible populations, indicating that E.adenophorum adaptability to high temperature may be associated with ATPase activity and thus to invasion success.