We assessed the psychometric properties of the Social Behavior Questionnaire (SBQ), a 30-item questionnaire evaluating social (e.g., disruptive behaviors, bullying) and emotional problems (e.g., anxiety, depression) among children aged 3.5-12 years. Children (n = 1,950, 50.21% boys) were drawn from the Quebec Longitudinal Study of Child Development. Mothers reported the frequency with which children presented social and emotional behaviors from 3.5 to 8 years of age, and teachers from 6 to 12 years. We assessed internal structure using Confirmatory Factor Analysis, reliability using Cronbach's alpha, and convergent and discriminant validity using a multitrait-multimethod (MTMM) approach. The six-factor (emotional distress, withdrawal, impulsive/hyperactive/inattentive, disruptive behaviors, prosocial behaviors, and peer relationships difficulties) structure of the SBQ showed good fit from ages 3.5 to 12 years. Reliability estimates were good to excellent (alphas > 0.7), and MTMM showed good convergent and discriminant validity. Overall, the SBQ presented good psychometric properties with a large population-based sample aged 3.5-12 years. Further studies should assess its screening potential by investigating its convergent validity with diagnostic information.