Identifying the latent structure of Oppositional Defiant Disorder (ODD) may have important clinical and research implications. The present study compared existing dimensional models of ODD for model fit and examined the metric and scalar invariance of the best-fitting model. Study participants were a diverse (38.8 % minority, 49.1 % boys) community sample of 796 children. Parents completed the Child Symptom Inventory and the DISC-YC ODD scales at child ages of 4, 5 and 6–7 years. When comparing single-factor (DSM-IV model), two-factor (oppositional behavior, negative affect), and three-factor models (one with dimensions of oppositional behavior, negative affect, antagonistic behavior; a second with dimensions of irritable, hurtful, and headstrong), the two-factor model showed the best fit. The two-factor model showed configural, metric and scalar invariance across gender and age. Results suggest that, among existing models, ODD is best characterized as two separate dimensions, one behavioral and one affective, which are comparable for both boys and girls in these age groups.