Larva of Anopheles gambiae ss were collected in the sites at Lwiro and the surrounding areas, to study the sensibility and resistance of these vectors in front of four insecticides in the entomology laboratory of medicine and parasitology, CRSN-Lwiro. The test was carried on the adult femele vectors, twenty five individuals whose age ranged from two and five days. Indeed, this test concerned four insecticids mainly perméthrine (0.75%), deltaméthrine (0.05%) two components of pyrethrinoïdes, malathion (5%) and lambdacyhalothrine (0.05%) largely used in public health for the vectorial control. After more tests, all the Anopheles population have been noticed sensible to all the precited insecticids. Within an hour of test, Anopheles gambiae presented a certain resistance to deltamethrine with a rate of mortality of 46.6%. Twenty four hours after, the rate of resistance for anopheles raised to 95.5%. Statistically, at .05, between permethrine, malathion and lambdacyhalothrine, the difference is not significant in term of resistance. However, the deltamethrine compared to the three insecticids cited above, displays a significant difference and the vectors are resistant. The vectors of malaria may display a certain resistance to the insecticids owing to their origin and concentration.