Malaria remains a significant public health challenge in Africa where it is the most important vector-borne disease. Nigeria bears the largest burden, with pregnant women and children under 5years being more affected. Although, long lasting insecticidal nets (LLINs) remain effective for control, its use has been suboptimal. Hence this study assessed, household ownership, physical integrity and use of LLINs among children. A community-based, cross-sectional study was carried out among 1642 households using a multistage sampling technique in Osun State, Nigeria. A pretested, interviewer-administered questionnaire was used to obtain information on socio-demographic characteristics and use among under-fives. LLINs were inspected for physical integrity and cleanliness. A binary logistic regression analysis was conducted to identify factors influencing LLIN use by under-fives. The mean age of children was 32.2 ± 16.5months. Most households, 1586 (96.6%) had an LLIN while 165 (10.4%) did not hang their net. Holes were present in LLINs in 360 (22.7%) households and 196 (12.4%) had dusty or stained nets. Most households, (1259; 79.4%), had at least one LLIN for every 2 household members and survey participants reported that 1331 (83.9%) under-fives slept under an LLIN the night before the survey. Factors associated with reported LLIN use were; older parents/guardians aged 50-59years (AOR: 3.02; 95% CI 1.50-6.09), having a post-secondary education (AOR: 2.56; 95% CI 1.31-5.00), having LLIN obtained < 12months (AOR: 4.27; 95% CI 2.39-7.64), households with one LLIN for every 2 members (AOR: 1.65; 95% CI 1.15-2.37) and households with clean nets (AOR 2.75; 95% CI 1.89-4.00) had increased odds of reported LLIN utilization by under-five children. Although LLIN ownership and reported use were high in this study, gaps exist between ownership and reported use of LLINs. About one-fourth of LLINs had poor physical integrity. To maximize LLIN effectiveness in households, it is important to ensure the continued free distribution of nets and emphasize messages to parents/guardians on proper care, maintenance, and use of nets.