The joint action of baygon insecticide with sumithion, diazinon, dursban, sumicidin and permethrin insecticides was studied against Culex pipiens resistant strain larvae. This strain was subjected to continuous laboratory selection with baygon for 15 successive generations. The results showed that the baygon produced synergistic effects with permethrin and diazinon. An additive effect was observed with sumicidin and sumithion; while an antagonism effect was only produced with dursban. The joint action of baygon with the insect growth regulator produced a synergistic effect with IKI after 24 hour of exposure period. However an additive effects were produced with IKI and bay sir after 48 &72 hours and 24, 48 &72 hours of treatments respectively. The obtained results showed the possibility of using the baygon insecticide in combinations with permethrin, diazinon, sumicidin, sumithion and with the insect growth regulator (IKI and bay sir ) for controlling C. pipiens larvae.