Despite the free distribution of insecticide impregnated nets, malaria is still the cause of many deaths, particularly among children under 5 years old, casting doubt on the real use of these mosquito nets by parents. The present work aimed to identify the factors associated with the low use of mosquito nets. This was a cross-sectional study with an analytical aim, carried out in the locality of Fô-Bouré (Sinendé) in 2019 among children under 5 years old and their parents. A cluster random sampling was carried out according to the WHO technique. The dependent variable was the low use of LLINs and the independent variables were: socio-demographic, economic, relative to parents' knowledge of the causes and control methods of malaria. Results: The factors identified as associated with the low use of LLINs were: female sex (p = 0.0059), low level of education (p = 0.0001), free mode of acquisition (p = 0.0476), poor knowledge of control methods (p = 0.0389), type of house: mud or tent house (p = 0.0034), unsanitary immediate environment (p = 0.0002) and children's evening dressing style (p = 0.0001). Conclusion: A global development policy, especially in terms of education, sanitation and housing improvement as recommended by the "Roll Back Malaria" initiative is necessary to improve the rate of insecticide impregnated nets use.