Parenting behaviors play an essential role in healthy youth development, and poor parenting behaviors place youth at risk of developing problem behaviors, mental health problems, and difficulties in emotional self-regulation. This study explores the associations among various types of parent anxiety, parent emotion regulation abilities via self-report and high-frequency heart rate variability (HF-HRV), and parenting behaviors. This study also tests a model where emotion regulation is hypothesized to buffer the link between parent anxiety and less effective parenting behaviors or where poor emotion regulation strengthens the association between anxiety and less effective parenting. Caregivers of adolescents (N = 80) completed self-report measures of parenting behaviors, anxiety, and emotion regulation. Caregivers also completed an HF-HRV assessment during a resting state and a mild stress task. Results indicate that parent anxiety is associated with parenting behaviors and that parent emotion regulation is also associated with parenting with three significant moderating effects of HF-HRV stress reactivity. Trait anxiety interacted with low HF-HRV reactivity to predict negative parenting practices and poor monitoring, and somatization interacted with low HF-HRV reactivity to predict poor monitoring. Findings suggest that poor emotion regulation, indexed by physiological reactivity to stress, may strengthen the relationship between parent psychopathology and poor parenting behaviors. This study did not find a buffering effect of optimal emotion regulation abilities on the relationship between anxiety and parenting. Our findings add incremental insight into the way we conceptualize how anxiety and emotion regulation affect parenting behaviors.