Mixed findings with regard to cardiovascular reactivity (CVR) and posttraumatic stress disorder (PTSD) have suggested a need to further explore the nature of this relationship and factors that might explain differences in reactivity across and within samples. In the present study, the severity of PTSD symptoms was investigated in relation to CVR among young women. In addition, we examined whether severity within PTSD symptom clusters and level of dissociative symptoms were related to CVR. Heart rate, systolic and diastolic blood pressure, cardiac output (CO) and total peripheral resistance (TPR) reactivity in response to an oral speaking task were assessed for 58 young trauma-exposed civilian women with varying levels of PTSD symptomatology (from no symptoms to high severity of PTSD). The PTSD severity sub-scores for the DSM-V symptom clusters and total PTSD severity were based on structured interview (Clinician Administered PTSD Scale), and dissociative symptoms were assessed using the Dissociative Experiences Scale. Severity of total PTSD symptoms was associated with greater CO reactivity (