Susceptibility test of 0,223% d-alletrin against adult Cx. p. quinquefasciatus was conducted in the Entomology Laboratory of Health Ecology Research Centre in Jakarta. A randomized complete design was performed using 4 replicates for each application. Regression analysis was applied to analyse the data. The adult mosquitoes of 3 days old, blood-fed females was involved in the test. The indicator of 0,223% d-alletrin effectiveness was knock-down time and mortality. The results showed that d-alletrin was able to knock-down 20% of Cx. p. quinquefasciatus within one hour. Based on regression analysis (Y = 3,31 + 0,31 X) knock-down time 50 (WLso) was reached at the 170th minute. While 50% mortality was reached at the 198th minute (Y = -3,6 + 0,37 X). After 6 hours of exposure all of the mosquitoes were knocked-down and 91% were killed and after 7 hours of exposure all of the mosquitoes were killed.