Background: Diagnosis of hematological cancer affects patients and caregivers as a unit. Few studies have focused on the relationship between hematological cancer patients and their caregivers. Objective: To explore (a) the interaction between patients receiving treatment for hematological cancer in a hematology-oncology clinic and their family caregivers and (b) perceived changes in lives of patients receiving treatment for hematological cancer in a hematology-oncology clinic and their family caregivers. Methods: We used a qualitative descriptive design with a dyadic approach. The study sample included 11 patients with hematological cancer and 11 family caregivers selected through purposive sampling. In-depth interviews were conducted using a semistructured interview format. Results: As a result of a content analysis, 3 themes emerged: hidden emotions, companionship,and life changes. Both the patients and the family caregivers described coping by hiding their feelings, thoughts, and needs and reducing communication with each other. Dyadmembers described commitment to each other and an increase in confidence. In addition, the patients and the family caregivers experienced changes in their roles and perspectives during the diagnosis and treatment process. Conclusion: Patients with hematological cancer and family caregivers need nurses' support. Nurses should be prepared to provide patient-caregiver--based interventions. Implication for Practices: It is important that nurses take action to strengthen the relationship between patients and their caregivers, particularly with a focus on carrying out interventions to improve communication between them. Nurses can also strengthen dyads' coping by drawing attention to positive developments in their perspectives and relationships.