The dengue, malaria and filariasis are serious global disease which caused by the mosquitoes, Anopheles stephensi, Aedes aegypti and Culex quinquefasciatus. These species cause high morbidity and mortality to the human population and the development of resistance to chemical insecticides resulting in rebounding vectorial capacity. Plants may be alternative sources of mosquito control agents. The GC-MS analysis of grape fruit pedicel was done and five major compounds were identified in the methanolic grape pedicel extract namely, N- Hexadecanoic Acid, 1,E-11,Z-13-Octadecatriene, 9,12- Octadecadienoic Acid, 9-Octadecynoic Acid and 6,8- Dodecadien-1-OL (6Z,8E). The mosquitocidals activity of methanol extracts from grape fruit pedicel against immature and adult of An. stephensi, Ae. aegypti and Cx. quinquefasciatus (L.) were studied. After 24 hrs the mortality was noted and Lethal Concentration (LC50) was calculated against An. stephensi, Ae. aegypti and Cx. quinquefasciatus. The LC50 of An. stephensi were 133.263ppm, 178.275ppm, 235.619ppm, 284.472ppm and 380.630ppm for I, II, III, IV Instar and pupae, respectively. Similarly, LC50 for Ae. aegypti were 89.093ppm (I Instar), 196.560ppm (II Instar), 241.043ppm (III Instar), 323.565ppm (IV Instar) and 363.515ppm (pupae) and for Cx. quinquefasciatus were 190.073ppm, 261.693ppm, 295.404ppm, 289.067ppm and 348.430ppm for I Instar, II Instar, III Instar, IV instar and Pupae, respectively. After the treatment of grape pedicel extract the percentage of egg hatchability (Ovicidal activity) was observed. No eggs were hatched out after 400ppm of three mosquito species. In ovipositional deterrent study the number of eggs laid in control and treatment water was observed and based on this the Effective Repellency (ER) was calculated. The ER ranging from 69.83% to 88.43 % for An. stephensi; 72.18% to 89.14% for Ae. aegypti; 69.66% to 88.81% for Cx. quinquefasciatus, was investigated. It is thus concluded that the grape fruit pedicel extract has an effective toxicity against An. stephensi, Ae. Aegypti and Cx. quinquefasciatus. Hence, this pedicel extract can be used as an insecticide.