Background: Autologous bone marrow transplantation is an intervention for a variety of life-threatening diseases. Stem cells transplantation procedures continue to be improved, making transplantation a treatment option for many patients. The unique and intensive nature of this treatment requires distinctive knowledge and care during and post the entire transplant course . Aim to assess the knowledge of the caregivers of post autologous bone marrow transplantation patients  at home. Research Design: A descriptive study. Sample:  A convenient sample was comprised a total number of 143 patients, during the six months attend the follow up clinic at bone marrow transplantation unit. Setting: The study was conducted at outpatient follow-up clinics, bone marrow transplantation unit in Sheikh Zayed Specialized Hospital, National Oncology Institute, and Nasser Institute.  Tools: Two tools were used for data collection. First tool: A self-administered questionnaire of patients and their caregivers' demographic data. Second tool: Caregivers' knowledge toward post autologous bone marrow transplantation patients at home. Results: This study indicated that, most of caregivers of the studied sample were totally need to improve their knowledge, and there were significant association between caregivers' demography and their knowledge.  Conclusion: Caregivers had poor knowledge of post autologous bone marrow transplantation. Recommendation:  Although caregivers had adequate knowledge on some aspects, gaps were identified. There is a need for educational interventions and discharge plan to upgrade knowledge, post autologous bone marrow transplantation patient at home.