Mindfulness (tendency to attend to present experience without expectation or judgment) is generally considered to be an adaptive way of responding to emotional experience. Anxiety sensitivity can be conceptualized as a maladaptive response (fear) to arousal-related somatic sensations commonly associated with anxiety. Emotion regulation strategies are learned in the context of early attachment relationships, and adult attachment styles have been linked to both mindfulness and anxiety sensitivity. This study examined whether mindfulness facets (observe, describe, act with awareness, accept without judgment) would mediate associations between attachment and the dimensions of anxiety sensitivity (physical, social, cognitive concerns). Multiple mediation analyses showed that observe mediated the relation between attachment anxiety and physical concerns, and accept mediated the relation between attachment anxiety and social concerns. Accept, aware, and observe each mediated the relation between attachment anxiety and cognitive concerns. Only accept mediated the association between attachment avoidance and the three anxiety sensitivity dimensions. Findings suggest the importance of measuring mindfulness as a multidimensional construct, and the value of assessing attachment style and incorporating mindfulness elements in interventions designed to reduce anxiety sensitivity.