【Background】Mikania micrantha (Asteraceae) and Aleurodicus disperses (Aleyrodidae) are two invasive species of China with non-parasitism. The study sought evidence for ecological control of A.disperses by M.micrantha by its plant-based alkaloids. 【Method】The laboratory bio-activities and field effects of M.micrantha extracts were examined using four extraction methods (cool maceration, Soxhlet extraction, cool maceration followed by Soxhlet extraction, warm maceration). M.micrantha extracts were tested on A.disperses using test tube residual film and field spray method. 【Result】Among the four different extraction methods, Soxhlet extraction and warm maceration showed higher extraction rate (9.90% and 9.35%, respectively) followed by cool macerationwithSoxhlet and cool maceration extraction methods (extraction ratio of 7.73% and 4.50%, respectively). The laboratory bioassay results indicated no significant difference among the bio-activities of M.micrantha extracts prepared using different extract methods on A.disperses under laboratory conditions. However, significant differences were found under field conditions: Soxhlet extraction and warm maceration extracts had higher effect than those of cool macerationwithSoxhlet and cool maceration. All extracts showed good effects on A.disperses, and the best method (Soxhlet extraction), at 100× times dilution, killed over 75% of A.disperses individuals after 7 days. 【Conclusion and significance】Extracts of M.micranthashowed inhibition against another invader, A.disperses, so its success may involve plant-based alkaloids.