Previous research investigating the influence of Type D personality on cardiovascular reactivity to stress in healthy young adults is somewhat mixed. The present study sought to investigate this question using an ecologically valid laboratory stressor. Beat-to-beat blood pressure and heart rate were measured in 77 healthy young adults during exposure to multitasking stress. Mood and background stress were both associated with Type D personality when Type D was conceptualised as a dimensional construct, with less robust findings observed using the traditional dichotomous typological approach. However, the continuous Type D construct added limited predictive value of the self-report measures above that of its constituent components, negative affectivity (NA) and social inhibition (SI). Further, an inverse relationship between the continuous Type D construct and blood pressure reactivity to multitasking stress was observed. In summary, our findings suggest that Type D personality is predictive of blunted cardiovascular reactivity to stress in healthy individuals when Type D is considered as a dimensional construct and the independent influence of NA and SI is controlled for. Further, our findings suggest that Type D does not predict additional variance in mood and background stress above that of NA and SI when these constituent factors are considered independently.