Background: Young adults with autism spectrum disorder's (YA-ASD) ability to manage their healthcare needs is imperative as they transition to adult care. Method: This study evaluated YA-ASD's knowledge and care-seeking behavior for Physical and Mental Health (PH/MH) conditions. Caregivers (n = 501), of YA-ASD 16-25 years completed surveys. This study examined the extent to which YA-ASD could describe and seek care for their physical and mental health conditions (i.e. describing and care-seeking behaviors). Multivariate analyses further evaluated YA-ASD's ability to and predictors of describing and care-seeking behaviors. Results: YA-ASD had high rates of PH and MH conditions. Describing and careseeking behavior was significantly higher for PH versus MH conditions (p < .001). Regression analysis showed similar predictors for describing and care-seeking behaviors regardless of condition type. Intellectual disability and ASD-symptom severity were strong predictors (p < .001). Conclusions: Results reveal a need for interventions focusing on empowering YAASD to manage MH conditions.