Previous studies found associations between children and sex in child sex offenders (CSOs) using the Implicit Association Test (IAT). We used a modification of this task, the Single Category–Implicit Association Test (SC-IAT) to unravel child-sex associations in CSOs. Using the SC-IAT, we were able to test whether CSOs indeed hold stronger child-sex associations relative to adult-sex associations, compared to adult sex offenders and nonoffenders. Furthermore, we examined whether contact CSOs differed from noncontact CSOs in their child-sex associations. The hypothesis that CSOs would have stronger child-sex associations, relative to their adult-sex associations, than adult sex offenders and nonoffenders was confirmed. No difference between contact CSOs and noncontact CSOs was found. Although the Sex SC-IAT was able to distinguish CSOs from nonoffenders, the sensitivity and specificity of the test was poor (AUC of .65) and needs refinement. The results of this study support the existence of a child-sex association as a distinctive characteristic of CSOs. These findings are discussed in the context of theories on deviant cognitions in CSOs and risk for sexual offending.