The overall aim of this study was to ascertain how the principal caregivers of oncology patients placed under Palliative Care envision the act of caring and the imminent loss of a family member, evaluating how this affects their levels of emotional stress. Ten caregivers aged between 31 and 73, who were also family members, participated in the study, 80% of the sample being female. Oncology patients, accompanied by their respective caregivers, were cared for at a hospital in upstate São Paulo. For the data collection, a semi-structured interview script and Lipp's Stress Symptoms Inventory (LSSI) for adults were used. Data analysis was both quantitative and qualitative. The results showed that 100% of the respondents suffered from stress, of which 60% were in the near-exhaustion phase and 40% in the resistance phase. It was found that the act of caring is envisioned by caregivers as bringing about change, both in daily routines and in interpersonal family relations, that create difficulties, necessities and growth during the terminal stages of the patient's life. Caregivers' experiences of the imminence of the death of a loved one gave rise to assorted feelings, such as fear, despair, impotence, thinking about one's own finiteness and the avoidance of thoughts of death. It is important to emphasize that, despite the small sample size of the study, the results are consistent with other studies, underscoring the need to devise specific, effective and continuous interventions with the principal caregivers of patients with no hope of a cure, for the good of their own health, improvement in the quality of life and preparation for potential loss and separation.