Mosquitoes are small irritating creatures that makes nuisance, their bites give itchy sensation, bumps and not only that but most importantly it transmit several vector borne diseases such as Malaria, Dengue, Chikungunya, Japanese encephalitis, filariasis etc. The mosquito vector control programme continues to rely on chemical insecticides, which causes resistance in vector species. Alternative methods based on phytochemical sources could be used to eliminate the Malaria, dengue, Chikungunya, and Zika virus vectors. In the present study we extracted Phlogacanthus thyrsiformisleaf and flower and the leaf of Clerodendrum glandulosum Coleb. with various solvents viz. petroleum ether, chloroform, ethyl-acetate and methanol against the 4th instar larvae of three species of mosquito, Anopheles stephensi, Aedes aegypti and Culex quinquefasciatus. All the extracts at concentration of 25, 50, 100, 200 and 300 ppm caused varied level of mortality after 24 h of post treatment. Among the extracts methanol Phlogacanthus thyrsiformis flower extract showed the highest larvicidal activity with LC50 and LC90= 36.157, 143.995 ppm for Anopheles stephensi; 55.088, 199.27 ppm for Aedes aegypti; 69.313, 267.125 ppm for Culex quinquefasciatus. The current study discovered that Phlogacanthus thyrsiformis methanol flower extract has remarkable larvicidal efficacy against medically important vector mosquitoes, making this plant product promising as an alternative to chemical insecticide in mosquito control programmes.