【Aim】 We investigated the effect of drought stress on Conyza canadensis seed germination and radicle growth, aiming to provide a scientific basis for the prevention and control of C. canadensis invasion. 【Method】 Mature C. canadensis seeds from the current year were treated with distilled water and polyethylene glycol (PEG) solutions of different mass fractions (5%, 10%, 15%, 20%, and 25%). These mass fractions represented mild, moderate, severe, extreme, and extremely severe drought stress intensities, respectively. We measured various indices, including daily relative germination rate, germination rate, and germination potential, to analyze the seed germination potential of C. canadensis. Additionally, we measured seedling root width, root length, average root diameter, root area, total number of root tips, and root branching number to assess radicle growth capacity. Seed recovery germination was also measured. 【Result】 Germination indicators were highest for C. canadensis seeds not exposed to drought stress. As drought stress intensity increased, seed germination indicators decreased, and C. canadensis seeds did not germinate under extremely severe drought stress. Compared with control seeds, mild drought stress and severe drought stress had no significant effect on the average root diameter of C. canadensis but did promote the growth of lateral and indefinite roots. These studies summarize the impact of PEG induced drought stress on the germination and radicle growth of C. canadensis seeds. C. canadensis seeds do not germinate under drought stress with a PEG mass fraction of 20.13%. Seeds do not germinate under extreme and severe drought stress, but when water conditions become sufficient, seeds regain the ability to germinate. 【Conclusion】 These results suggest manual removal of plants before C. canadensis seeds have matured or the planting of drought-resistant, fast-growing, well-rooted, and highly competitive plants in C. canadensis invasion areas to control the growth and development of C. canadensis.