Autism spectrum disorders (ASD) are among the most common childhood neurodevelopmental disorders. Identification of risk and protective factors are necessary to improve the guidance of prevention and intervention strategies. Our study aims to determine the potential risk and protective factors in ASD in the Lebanese population. Our case-control study included 100 ASD patients and 100 healthy matched controls recruited from all the Lebanese districts. The data collected from the questionnaires was analyzed using SPSS 23.0. Independent Student T-test and Chi-Square test were carried out for the bivariate analysis of the data. In addition, the variables revealing a -value < 0.05 were used for the multivariate logistic regression analysis. Multivitamins intake, especially omega 3 and vitamin B (Odds Ratio (OR) = 0.257; 95% Confidence Interval (CI) [0.115-0.579]), rich cereal diet (OR = 0.212; 95% CI [0.089-0.510]), and supplementation in iron during pregnancy (OR = 0.229; 95% CI [0.083-0.627]) were identified as protective factors against ASD. On the other hand, stress during pregnancy (OR = 6.339; 95% CI [2.845-14.125]), the presence of ASD patients in the family (OR = 7.878; 95% CI [1.877-33.065]) and the presence of attention deficit hyperactivity disorder (ADHD) patients in the family (OR = 6.981; 95% CI [1.362-35.789]) were associated with ASD. This study shed light on risk and protective factors associated with ASD in the Lebanese population. Further rigorous research, taking into consideration these factors, is needed to assist in early detection, prevention and subsequent intervention targeting ASD and its associated comorbidities, given that our study is not experimental and does not prove causality.