Understanding the overlap of symptoms between oppositional defiant disorder (ODD) and obsessivecompulsive disorder (OCD) experienced by youth is pertinent for accurate diagnosis. A quantitative, retrospective, cross-sectional design format was used to assess the relationship between ODD and OCD in addition to evaluating the difference in ODD severity and symptoms based on OCD severity. Symptoms and severity ratings of ODD and OCD were collected from youth diagnosed with ODD (N = 179). Fisher's exact test and a Wilcoxon signed-rank test were performed. There were significant relationships between frustration related to obsessions and compulsions and the ODD symptoms of annoyance and anger. Results suggested that OCD severity predicted an increase in scores for ODD severity and symptoms.