Objective The aim of this study is to investigate the presence of dissociative symptoms and whether they are related to childhood trauma and obsessive-compulsive symptoms in bipolar disorder type II (BD-II). Methods Thirty-three euthymic patients (HDRS<8, YMRS<5) and 50 healthy subjects were evaluated by SCID-I and SCID-NP. We excluded all first and second-axis comorbidities. All patients and healthy subjects were examined with the Dissociative Experiences Scale (DES), Childhood Trauma Questionnaire (CTQ-53), and Yale-Brown Obsessive-Compulsive Disorder scale (Y-BOCS). Results In pairwise comparisons between the BD-II and control groups, the total CTQ, emotional abuse, emotional neglect, DES, and total Y-BOCS scores in the BD-II group were significantly higher than those in the control group (p < 0.05). There were five cases with DES scores over 30 (15.2%) and one case (2%) in the control group. DES was weakly correlated with total CTQ and Y-BOCS in patients diagnosed with BD-II (r = 0.278, p < 0.05 and r = 0.217, p < 0.05, respectively). While there was no correlation between total CTQ and Y-BOCS, the CTQ sexual abuse subscale was found to be related to Y-BOCS (r = 0.330, p < 0.05). Discussion These results suggest that there is a relation between childhood traumas and obsessive-compulsive symptoms, or that dissociative symptoms are more associated with anxiety than obsessive symptoms, which prevents the increase of obsessive-compulsive symptoms in BD-II.