Objective: This study is carried out to determine the symptoms and information necessity on chemotherapy (CT) treatment of the women with breast cancer. Methods: A total of 170 women older than 18 years old, who receive CT with breast cancer diagnosis, are volunteered to participate in the study. Mixed method was used in the study. Data are collected using Descriptive Data Form, Interview Form and Memorial Symptom Assessment Scale. Results: As a result of the cluster analysis, four clusters and the symptoms within have been obtained. These are: pain, lack of energy, feeling drowsy, sweat, swelling of hands, and feet in the first cluster; feeling nervous, difficulty sleeping, feeling sad, worrying in the second cluster; nausea, feeling bloating, change in the way food tastes, hair loss, constipation in the third cluster; vomiting, diarrhea, problems with sexual interest, lack of appetite, dizziness, and weight loss in the forth cluster. Women's information necessity related to the CT are follows: the effects of CT, other treatment options beyond CT, complementary methods, the effect of the CT treatment on reproductive health and sexuality, nutrition, and symptom control. Conclusions: The results of this study will enable determination of symptom clusters, which health professionals are easier to focus on these symptoms. An understanding information need of patients can help to ensure that individual's coping strategies and self-management.