Objective: To evaluate the burden on family caregivers of children and adolescents in immediate post hematopoietic stem cell transplantation. Method: Study of quantitative nature, of analytical and traverse type, accomplished in two institutions of health with 31 caregivers of children and adolescents in immediate post transplantation. The data collection was accomplished between October of 2018 and June of 2019. The caregivers' social demographic profile was characterized, and the burden was evaluated by Caregiver Burden Scale. The descriptive statistics and the Spearman correlation were used. Results: It was obtained a burden global score of 2.4/4; the domains with larger scores were: general stress and frustration, both with 2.8/4. Conclusion: The understanding of how the family faces the challenges imposed by the immediate post hematopoietic stem cell transplantation guides the multiprofessional team a care centered in the family and to offer maximum support and guidance to the caregiver.