Post-traumatic stress disorder (PTSD) negatively impacts sexuality, yet few studies have evaluated which component of PTSD contributes to this known association. The present study examined which of four PTSD clusters (numbing, avoidance, intrusiveness, and hyperarousal) was most closely linked to sexual problems in a sample of 197 veterans from the Iraq or Afghanistan wars. Newly registered veterans completed a packet of questionnaires including standardized measures of PTSD and questions regarding sexual functioning. A stepwise logistic regression was performed to examine the relationship between symptom cluster and sexual functioning. As predicted, only the numbing cluster was retained in the regression model. The numbing cluster appears to be intimately tied to sexual functioning, assessment of which should be part of a comprehensive evaluation during the postdeployment readjustment phase. Those exhibiting numbing symptoms should be thoroughly assessed for sexual functioning problems and referred for treatment as necessary.