Throughout the year, the population of the right bank (Niamey) is confronted with the diseases and nuisances of culicidae. This study aims to make a systematic inventory of mosquitoes, to study their abundance and their specific richness. Mosquito larvae were collected using the dipping method, over the period July 2021 to June 2022, in Lake Lamordé and the rice fields of Kirkissoy. Stage three and four larvae were sorted and deposited in transparent tubs containing bedding water and fed. Emerged mosquitoes were counted, identified morphologically with a binocular loupe and a culicid identification key. During this study, 3947 larvae were collected of which 3033 evolved to the adult stage, i.e. an emergence rate of 76.84%. The genus Anopheles is more abundant in the lake (n=1238). In the rice fields, the genus Culex dominated (n=402). Statistical analysis showed that the mosquitoes were not evenly distributed in space and time. The taxonomic study identified 11 genera and species at the two sites. These were Anopheles gambiae, Anopheles pharaonsis, Anopheles squamosus, Anopheles rufipes, Anopheles nili, Anopheles funestus, Culex tritaenyohinchus, Culex decens, Culex aurentapex, Culex quinquefasciatus and Aedes aegypti. These results show that mosquitoes proliferate over a long period of the year and that appropriate control measures must be taken to prevent diseases and avoid nuisance caused by them.