Abstract : Oncology nurses are essential in palliative care for cancer patients, especially at end-of-life stages. Caring for terminally ill cancer patients is stressful, accompanied by negative and positive feelings, but oncology nurses have an unavoidable responsibility. However, little is known about oncology nurses' experience in the Kingdom of Bahrain caring for terminally ill cancer patients in their final weeks or days. This study aimed to explore the experience of oncology staff nurses in providing care for terminally ill patients in the Kingdom of Bahrain, and the research answered those questions: (a) What is the experience of oncology staff nurses in providing care for terminally ill patient? And (b) How does the experience of oncology nurses in providing care to terminally ill patients impact the quality of care provided to patients? A qualitative descriptive, interpretive exploratory research design was utilized for this study to explore the experience of oncology staff nurses with terminally ill patients, conducted in two hospital settings at Salmaniya medical complex (inpatient & outpatient) oncology department. The data were collected using a purposive sampling to include 15 oncologist nurses whose experiences were across various characteristics with different professional roles and qualifications. The data were collected through 15 semistructured interviews guided by a semi-structured interview protocol. Data were analyzed using Braun and Clarke's 2006 thematic analysis model without pretexting. The research findings revealed three key themes that emerged from thematic analysis: (1) exhausting versus rewarding experienced feelings; (2) Factors influencing Nursing care; (3) Moral Distress. End-of-life care in the Kingdom of Bahrain reflects and has been influenced by primary total nursing care. Oncology nurses reported suffering but also benefiting from their experiences. End-of-life cancer care training is needed and urged by oncology nurses, especially those younger and less experienced. Also, future studies are mandated to explore interventions to help overcome the challenges that are impeding nurses from providing high-quality care for terminally ill patients in the kingdom of Bahrain. Keywords: Terminally ill; Terminal Care; palliative care; an oncology nurse.