Purpose <p>Hematopoietic stem cell transplantation (HSCT) is a physically and psychosocially complex process for patients and their families, and nurses play a key role in coordinating patient care. This study aimed to explore nurses’ perspectives on caregiver engagement in the care of patients undergoing hematopoietic stem cell transplantation.</p> Methods <p>A qualitative descriptive design with purposive sampling was used. Data were collected through semi-structured interviews with eleven nurses working in a bone marrow transplantation unit in Ankara. The data were analyzed using thematic analysis.</p> Results <p>Five main themes and ten sub-themes were identified. The main themes were 1) Nurses’ expectations and caregiver involvement, 2) Impact of caregiver’s engagement, 3) Caregiver strain and challenges, 4) Support needs of caregivers, and 5) Nurses’ role in supporting caregivers.</p> Conclusions <p>Nurses perceived that caregiver engagement positively improves patient outcomes but also noted that this placed a significant burden on caregivers. Nurses play a pivotal role in addressing the challenges and supporting caregivers through emotional support, education, and advocacy. Targeted interventions, such as education, psychological support, and enhanced communication, are crucial for supporting caregivers effectively and improving the well-being of both caregivers and patients.</p>