Introduction: Work-related post traumatic stress disorder (PTSD) can develop in nurses. Pediatric oncology nursing is a potentially high-risk subspecialty for PTSD secondary to the nature of the work. This study aimed to describe the prevalence of PTSD symptomology and explore relationships between nurse psychological capital, workplace social supports, and PTSD symptomology in pediatric oncology nurses. Methods: The study utilized a cross-sectional correlational survey design. Pediatric oncology nurses working in direct patient care in the United States completed a demographics questionnaire, Psychological Capital Questionnaire (PCQ), Coworker Support Scale, Supervisor Support Scale, and the Post traumatic Checklist for Diagnostic and Statistical Manual of Mental Disorders (PCL-5). Descriptive and inferential statistics, including logistic regression models, were used to analyze data. A cutoff score of ≥31 on the PCL-5 was used to determine the prevalence of PTSD symptomology. Results: The sample included 424 nurses. The prevalence of PTSD symptomology was 13.4%. Work setting (inpatient), decreased coworker and leadership social support, and psychological capital were independently associated with PTSD symptomology. After controlling for covariates, only psychological capital was associated with PTSD symptomology. For a 1 unit decrease in PCQ score, pediatric oncology nurses were 4.25 times more likely to have PTSD symptomology. Discussion: PTSD prevalence rates in pediatric oncology nurses are aligned with rates found in other nursing specialties. Nurse psychological capital may play a protective role against PTSD symptomology. Implications for Future Research: Findings support PTSD as a serious workplace concern for nurses. Workplace programs that foster nurses' psychological capabilities should be considered to protect against the development of PTSD symptomology.