Background: Bipolar disorder is a mental disorder characterized by intermittent episodes of mania or depression, with an absence of symptoms in between. During these episodes, people with bipolar disorder exhibit disruptions in normal mood, psychomotor activity, the level of physical activity that is influenced by mood Aim of the study: Was to assess the effect of caregiver's expressed emotions on clinical outcomes of patients with bipolar disorder. Research design: Descriptive /correlations design was used in this study.  Setting: Psychiatric and Mental Health Hospital in Benha city, Qalubia Governorate. Subject: A purposive sample consist of (80) bipolar disorder patients and their caregivers from the previous study setting. Tools: Three tools were used for data collection. Tool (1):- a structured interviewing questionnaire sheet was used to collect data about socio demographic and clinical characteristics of the studied sample. Tool (2):- Camber Well Family Interview to assess patients families about their response to patients illness. Tool (3):- to assess symptoms of patients with mood disorders. Results: There was a positive statistically correlation between total caregivers' expressed emotion and total patients' clinical outcomes. Conclusion: Patients with high- expressed emotion caregivers have been found to have poorer management of their health condition and poorer clinical outcome than those with low- expressed emotion. Recommendations:  Designing a systematically continuous family intervention programs in psychiatric hospitals that provide proper information and psychological support