Background: Childhood trauma exposure has been associated with increase in the risk of psychiatric disorders and elevated levels of systemic inflammation. Our study will discuss the effect of adverse childhood experiences on Bipolar Disorder (BD) clinical characteristic and high sensitivity C-reactive protein (hs-CRP) level. Our aim is to to estimate the frequency of childhood trauma and its effect on bipolar disorder clinical characteristics and to assess the association between childhood trauma and serum level of hs-CRP in adult patients with bipolar disorder.Methods: The study included 91 bipolar patients who fulfilled the inclusion criteria. The diagnosis of BD was confirmed by Structured Clinical Interview for DSM-IV Axis I Disorders SCID-I. Confirmation of remission was done by Young Mania Rating Scale (YMRS) or Hamilton Depression Rating Scale (HAM-D). Semi-structured Clinical Interview clinical characteristics of the disorder were performed. The World Health Organization (WHO) Adverse Childhood Experiences International Questionnaires (ACE-IQ) was used to estimate the prevalence of childhood trauma among BD subjects and then a blood sample was collected from each participant to measure the hs-CRP. Results: About 93.4% of the studied bipolar patients had at least 1 childhood trauma (CHT). A statistically significant difference between the studied groups is reported in some clinical characteristics, regarding the number of depressive and the total number of mood episode, the type of the first episode, the presence of psychotic features, the noncompliance to medications, the suicidal attempts and Hs-CRP level.Conclusion: Presence of childhood trauma in patients with BD is common. It worsens its clinical course and is associated with higher adult inflammation.