Several active substances, belonging to the pyrethroid family, are used in the fight against mosquitoes. The use of pesticides is not without consequences for health and the environment. Several species of mosquitoes (Anopheles and Culex) are increasingly developing resistance to these active substances, which makes insecticides very little or not at all effective. The present study aims to evaluate the effectiveness of the most commonly used insecticides in the city of Niamey in order to produce data that can guide both decision makers and users in the choice of pesticides to use. To do this, the mosquito repellent products most commonly used in households were inventoried. Sensitivity tests were performed on adult mosquitoes with 25 mosquitoes per cage, including two control cages and three test cages. Aerosol cans were sprayed for ten seconds while smoke bombs were lit and placed in the room. For each product, knockdowns were recorded every ten minutes for one hour and mortalities twenty-four hours after the test. Sensitivity testing revealed that mosquitoes are resistant to the products tested as indicated by low mortality rates ranging from 19-61%, lower than the WHO reported mortality rate (80%) for insecticide resistance.