Objective: Bipolar disorder (BD) is a serious burden for patients and family members due to recurrent mood episodes, hospitalizations, and loss of productivity. The goal of this study is to examine how psychoeducation affected the caregivers of bipolar patients' levels of emotional expression, stigmatization, loneliness, and mood symptoms. Method: This research is a quasi-experimental intervention study applied as a pretest-posttest design with a control group. The study included 20 patients with bipolar diagnosis and 20 caregiver spouses who were followed up in our outpatient clinic. Participants were divided into 2 groups as study and control group. The spouses in the control group were interviewed only to evaluate their situation. The study group received a 6-session (15 hours) psychoeducation intervention. We administered the Emotion Expression Scale (EES), Self-Stigma Scale-Family (SSI-F), UCLA Loneliness Scale (UCLA-LS), and DASS-21 Scale to the spouses of bipolar patients in the study and control groups before and after the psychoeducation program. Results: The mean age of the spouses in the study group was 43.4±7.04 years, the mean age of the spouses in the control group was 39±8.29 years and all of them were female. There was no significant difference between the mean scores of the SSI-F, EES, and DASS-21 scales of the spouses in the study and control groups before the training (p>0.05). After the psychoeducation program was applied to the spouses in the intervention group, a significant decrease was observed in the SSI-F, EES, and DASS-21 scale scores (p