ABSTRACT Objective To know the perception of children and adolescents undergoing cancer treatment about hospitalization. Methods Qualitative research conducted with 13 children and adolescents hospitalized for cancer treatment at a referral hospital in southern Brazil. Semi-structured interviews mediated by the drawing technique were conducted from May to November 2018. Data was submitted to inductive thematic analysis based on the theoretical framework of Brazil’s National Humanization Policy. Results Disturbances were detected in the professionals' communication with the hospitalized children and adolescents. The participants felt socially isolated and highlighted the importance of recreational activities during hospitalization. Conclusion Infant cancer is complex and needs multidisciplinary care during the treatment, enabling the organization of healthy and welcoming spaces that favor humanization of care.