Mosquitoes are one of the most lethal animals in the world and transmit many dangerous human pathogens, causing millions of deaths each year. The search for modern and better mosquito control is an endless effort almost all over the world. Phytochemicals are promising biological agents for getting rid of pests that are harmful to human and animal health and crops, they are inexpensive, biodegradable, and have diverse modes of action. The efficacy of acetone and hexane leaf extracts ofAcacia nilotica, Eucalyptus camaldulensis,andSalix safsafswas investigated against the 2nd and 4th larvae and pupae of two vectors,Culex pipiensandAedes aegypti. The results showed the obvious effectof A. niloticaextract on the mortality of mosquito larvae, the reduction of female eggs, and a higher mortality rate in sunlight than in shadow (fluorescein). Data from field trials revealed thatA. niloticaextracts had the greatest effect on larval reduction, reaching 89.8% in 24 h and having a 12-day stability. Polyethylene glycol, sesquiterpenes, and fatty acids were the most common compounds found inA. nilotica, E. camaldulensis,andS. safsafs, respectively. The acacia plant had promising larvicidal activity, safe and effective alternative to chemical insecticides.