Despite technological developments in the health field, the physical, emotional and social impacts of childhood cancer diagnosis are still enormous and long-lasting, as it manifests itself at a stage of life that is critical to human development. Therefore, this study sought to investigate the psychological impacts of positivity in pediatric oncology patients. A cross-sectional, qualitative study was conducted with children undergoing cancer treatment followed by the pediatric oncology sector of a reference hospital of the Unified Health System (SUS), in Pernambuco, from September 2021 to August 2023. Data collection was carried out through semi-structured audio-recorded interviews with the participants' consent, transcribed in full and analyzed according to Laurence Bardin's content analysis technique. Ten children participated in the study, four females and six males, aged between 8 and 12 years, an average of 9.9 years. The results pointed to the protective function of positivity in the face of stressful events, as a psychic strengthener linked to the adaptive management of limitations and difficulties arising from pediatric oncology treatment.