Larvicidal activity of crude hexane, ethyl acetate, petroleum ether, acetone, and methanol extracts of the leaf of five species of cucurbitaceous plants, Citrullus colocynthis, Coccinia indica, Cucumis sativus, Momordica charantia, and Trichosanthes anguina, were tested against the early fourth instar larvae of Aedes aegypti L. and Culex quinquefasciatus (Say) (Diptera: Culicidae). The larval mortality was observed after 24 h of exposure. All extracts showed moderate larvicidal effects; however, the highest larval mortality was found in petroleum ether extract of C. colocynthis, methanol extracts of C. indica, C. sativus, M. charantia, and acetone extract of T. anguina against the larvae of A. aegypti (LC₅₀ = 74.57, 309.46, 492.73, 199.14, and 554.20 ppm) and against C. quinquefasciatus (LC₅₀ = 88.24, 377.69, 623.80, 207.61, and 842.34 ppm), respectively. The petroleum ether extract of C. colocynthis and methanol extract of M. charantia were more effective than the other extracts. This is an ideal eco-friendly approach for the control of the dengue vector, A. aegypti, and the lymphatic filariasis vector, C. quinquefasciatus.