Background and Aims: We used population record linkage (NSW Child Development Study; NSW-CDS) to determine developmental risk profiles at age 5 years for later psychotic and affective dis- orders, comprising vulnerabilities indexed by the Australian Early Development Census (AEDC). Of interest were shared and distinct features of risk profiles for children with parental diagnoses of schizophrenia (SZ), bipolar disorder (BD), affective disorders (AD), or a combination of SZ and BD (SZ/BD). Methods: Participants were 69,116 children with linked parental health records and AEDC data. Children with at least one parent with SZ (N = 885), BD (N = 517), AD (N = 4,536), or SZ/BD (N = 1186) were determined. Sets of AEDC indicators of vulnerability on physical, social, emotional, and language/cognitive domains that predicted membership of each risk group (relative to children without such parental history) were determined using multinomial logistic regressions. Results: Risk for SZ, BD, and AD comprised vulnerabilities in domains of general physical and social competencies, anxious and fearful behaviour, hyperactivity and inattention, and basic numeracy. The profile for SZ risk was distinguished from other groups by limited readiness to explore new things, while all vulnerability indicators for BD were shared with those for SZ and AD. Risk profiles for SZ/BD closely resembled that for AD; aggressive behaviours were common to both AD and SZ/BD, but did not emerge in risk profiles for SZ or BD alone. Conclusions: Developmental risk profiles for psychotic and affective disorders in early childhood share many features representing physical, social, emotional, and cognitive vulnerabilities, with implications for the early detection of risk for severe mental disorders