Insecticides susceptibility tests were conducted on Culex pipiens larvae from both Doha and Al-Rayan. The insecticides used were chloropyrifos, propetamphos (Organophosphorous), cyphenothrin, cyfluthrin (Synthetic) and etofenprox. Larvae in Al-Rayan district were more susceptible to all insecticides than in Doha. The chlorophyrifos and cyfluthrin were the most effective larvicides, cyphenothrin was moderate and propetamphos and etofanprox were the least ones.