The role of behavioral inhibition (BI), parental rearing, and adverse life events in the development of obsessive–compulsive disorder (OCD) is unresolved. We prospectively examined whether BI and perceived parental rearing predicted the subsequent first onset of OCD and whether BI moderated the association between perceived parental rearing/adverse life events and the first onset of OCD. Data come from a prospective-longitudinal study among community adolescents and young adults (aged 14–24) who were followed up over 10 years (N = 2210). OCD and adverse life events were assessed with the DSM-IV/M-CIDI. BI and parental rearing were assessed by self-report. In adjusted logistic regressions, BI (risk ratio, RR = 8.8,95% confidence interval, CI,[3.3,23.2]), both the social (RR = 2.6,95%CI[1.04,6.3]) and nonsocial fear (RR = 4.5,95%CI[2.3,8.6]) components, and paternal rejection (RR = 3.9,95%CI[1.6,9.7]) predicted OCD. Social BI moderated the association of adverse life event (RR = 11.98,95%CI[1.8,82.1]) and paternal overprotection (RR = 5.5,95%CI[2.1,14.8]) with OCD. Nonsocial fear BI moderated the association between paternal emotional warmth (RR = 0.37,95%CI[0.1,0.99]) and OCD. BI and paternal rejection were associated with an increased risk of first onset of OCD. Individuals with high social BI who experienced paternal overprotection or any adverse life events may profit from early targeted prevention. Emotional warmth may buffer the association between nonsocial fear BI and OCD.