This pilot study aimed to assess the feasibility and possible effects of the "PalliActive Caregivers," nursing intervention, on the uncertainty in illness and quality of life of family caregivers of patients with cancer receiving palliative care. This pilot study used a randomized controlled design. The participants were 80 family caregivers. The experimental group received the novel "PalliActive Caregivers" intervention. Data were collected using a sociodemographic form, the Uncertainty in Illness Scale, the Quality of Life scale, and an Intervention satisfaction questionnaire. The caregivers who received the intervention "PalliActive Caregivers" reported a high degree of satisfaction (9.74 on a 10-point scale). The intervention showed a significant decrease in uncertainty regarding illness in the experimental group (P = .009), as well as a significant decrease in the psychological well-being of quality of life within the experimental and control groups, before and after the intervention (P = .013, P = .010). It is recommended that future studies using the "PalliActive Caregivers" intervention examine the effects on other variables such as the burden of patient's symptoms, caregiver burden and rewards, self-efficacy in symptom management, competence, unmet needs, and satisfaction with care.