This study examined the relationship between coping styles and ICD-11 PTSD and Complex PTSD in a large sample of Ukrainian Internally Displaced Persons. Data were collected in 2016 using self-report measures from all Ukrainian oblasts not occupied by Russian forces. In total, 13.1% of people met diagnostic requirements for Complex PTSD, and 7.8% for PTSD. Higher levels of avoidant coping were evident in those meeting diagnostic requirements for PTSD and Complex PTSD compared to those not meeting requirements for either. Mental health interventions targeting avoidant coping might be particularly useful in reducing the burden of traumatic stress among war-affected Ukrainians.