<p>The botanical insecticide, pyrethrum and its synthetic derivatives, pyrethroids, are used globally for controlling human disease vectors including <i>Aedes albopictus</i> and <i>Aedes aegypti</i>, two principal vectors of dengue and Zika viruses. Pyrethrum and two other polyfluorinated pyrethroids, dimefluthrin and meperfluthrin, are commonly used in the mosquito coils in China for mosquito control. However, the basic information on knockdown and toxicity of these insecticides against <i>Aedes</i> remains limited, especially in pyrethrum. The aim of this study was to compare the activities of these insecticides to two aedes mosquito strains with different bioassays. We assessed knockdown activity of pyrethrum, dimefluthrin and meperfluthrin against insecticide-susceptible <i>Ae. albopictus</i> and <i>Ae. aegypti</i> by fumigation bioassay and impregnated paper bioassay. Dimefluthrin and meperfluthrin exhibited higher knockdown and insecticidal activities than pyrethrum in two mosquito strains by both bioassays. Dimefluthrin and meperfluthrin elicited higher knockdown rates against <i>Ae. albopictus</i> than <i>Ae. aegypti</i> in both bioassays. The knockdown rate of pyrethrum against <i>Ae. albopictus</i> was higher than <i>Ae. aegypti</i> in impregnated paper bioassay, while it was by contraries in fumigation assay. Furthermore, the knockdown rate and mortality of all three insecticides were significantly increased by the pretreatment exposure of piperonyl butoxide (PBO) in both species. This study assessed knockdown activities of volatile pyrethroids and pyrethrum in two <i>Aedes</i> species using two different (routes of entry) bioassays. Both pyrethrum and volatile pyrethroids are potent knockdown agents, particularly against <i>Ae. albopictus</i>. PBO enhanced knockdown by pyrethrum, dimefluthrin and meperfluthrin, suggesting a role of P450s in the metabolism of polyfluorinated pyrethroids.</p>