Mosquitoes are the vectors of a number of human and zoonotic disease pathogens affecting human and animal hosts, including those that cause malaria, filariasis, Japanese encephalitis (JE), and dengue and yellow fevers. In view of the fact that mosquitoes develop genetic resistance to synthetic insecticides and even to bio pesticides such as Bacillus sphaericus the application of easily degradable botanicals for the control of mosquitoes is recommended. The present study determines the repellent activity of Ageratina adenophora (A. adenophora) (Spreng.) King & H. Rob. (Family: Asteraceae) extract against the dengue vector, Aedes aegypti (Ae. aegypti). The repellent efficacy was determined against Ae. aegypti mosquito species at three concentrations viz., 1.0, 2.5 and 5.0 mg/cm2 under the laboratory conditions. The methanol extract of A. adenophora found to be more repellency than the other extracts. A higher concentration of 5.0 mg/cm2 provided 100% protection up to 120 minutes, the lower concentration of 2.5 and 1.0 mg/cm2 provided 100 % protection up to 90 and 60 minutes, respectively. The results clearly show that repellent activity was dose dependent. From the results it can be concluded the crude methanol extract of A. adenophora was an excellent potential for controlling the dengue vector mosquito Ae. aegypti.