Background: Critically ill patients are at increased risk of developing malnutrition-related complications because of physiological changes, suboptimal delivery, and reduced intake. Strategies to improve nutrition during critical illness recovery are required to prevent iatrogenic underfeeding and risk of malnutrition. The purpose of this study was to assess the feasibility and acceptability of a novel family-centered intervention to improve nutrition in critically ill patients. Materials and Methods: A 3-phase, prospective cohort feasibility study was conducted in 4 intensive care units (ICUs) across 2 countries. Intervention feasibility was determined by patient eligibility, recruitment, and retention rates. The acceptability of the intervention was assessed by participant perspectives collected through surveys. Participants included family members of the critically ill patients and ICU and ward healthcare professionals (HCPs). Results: A total of 75 patients and family members, as well as 56 HCPs, were enrolled. The consent rate was 66.4%, and 63 of 75 (84%) of family participants completed the study. Most family members (53/55; 98.1%) would recommend the nutrition education program to others and reported improved ability to ask questions about nutrition (16/20; 80.0%). Family members viewed nutrition care more positively in the ICU. HCPs agreed that families should partner with HCPs to achieve optimal nutrition in the ICU and the wards. Health literacy was identified as a potential barrier to family participation. Conclusion: The intervention was feasible and acceptable to families of critically ill patients and HCPs. Further research to evaluate intervention impact on nutrition intake and patient-centered outcomes is required.