The study evaluates the resistance and susceptibility of adult femaleAnopheles gambiaes. l.,Aedes aegyptiandCulex quinquefasciatusmosquitoes sourced within Osogbo metropolis, Osun State, Nigeria to four groups of insecticides [Permethrin, Deltamethrin, Pirimiphos-methyl and DDT (Dichlorodiphenyltrichloroethane)] and the distribution of their larval habitat within the metropolis. Mosquito larvae of the three genera were collected during the wet season and reared to adult stage in the laboratory. Emerged adult female mosquitoes were exposed to insecticide impregnated papers of the four insecticide groups for 60mins using WHO kits to determine the knock down rate (kdr). Thereafter, they were transferred into holding tubes and left for 24hrs to assess their resistance and susceptibility according to the WHO protocol. Four types of larval habitats were identified (tires, ground pools, gutters and plastic containers).Anopheles gambiaes. l. showed the highest resistance to Permethrin (49%) (p = 0.04, p<0.05) while the highest susceptibility was recorded with Pirimiphos-methyl (69%) with the lowest against Permethrin (16%) (P = 0.002; p<0.05). The highest resistance ofA.aegyptiwas against OC-Control (45%) (p = 0.031; p<0.05). Permethrin had the highest susceptibility (60%) againstA.aegyptiwhile OC-control had the lowest (11%) (p = 0.005; p< 0.05).Culex quinquefasciatushad a lower resistance to OC-control (38%) as compared withAedes aegypti(45%). However, it was least susceptible to Pirimiphos-methyl (52%) and DDT (17%) respectively (p = 0.013; p<0.05). The susceptibility ofA.gambiaes. l. andC.quinquefasciatusto Pirimiphos-methyl andA.aegyptito Permethrin is an indication of the possibility of success if employed for vector control ofA.gambiaes. l.,C.quinquefasciatusandA.aegyptirespectively. This could be through their inclusion as active ingredients in insecticide treated nets (ITNs) and indoor residual spray (IRS) with a view to abating malaria and other life-threatening mosquito-borne diseases constituting global public health scourge.