Background: Disregard for rules, an important dimension of oppositional defiant and conduct disorders, is frequent during early childhood, but the development of its chronic form has not been studied during this key socialization period. This study aimed to describe the developmental trajectories of disregard for rules during early childhood and identify prenatal and postnatal predictors for a high trajectory. Methods: Participants were involved in a longitudinal study of a birth cohort followed yearly from 5 to 74 months of age (N = 1,942). Prenatal and postnatal predictors were measured by parental report at the beginning of the study, and parents reported child disregard for rules at five time points from 29 to 74 months of age. Results: Four groups of children followed distinct and stable trajectories of mother-rated disregard for rules: Very Low (approximately 9.1%), Low (56.9%), Moderate (29.7%) and Chronic (4.3%). As expected, male sex was a significant predictor of the chronic trajectory (OR = 1.76, CI = 1.09-2.83). Mothers' history of antisocial behavior (OR = 1.72, CI = 1.02-2.91), and postnatal depressive symptoms experienced by the mother (OR = 1.71, CI = 1.03-2.84) and the father (OR = 2.02, CI = 1.10-3.71) were also important independent predictors. However, contrary to expectations, children's difficult temperament and parenting at 5 months did not predict chronic disregard for rules beyond other risk factors. Conclusions: High disregard for rules is fairly stable during early childhood and is associated with risk factors identifiable before and shortly after birth which may be used for targeted prevention.