OBJECTIVE: To understand the vulnerability situations of adolescents and young people from rural areas undergoing cancer treatment. METHOD: Qualitative research, mediated by the health vulnerability framework, developed in an oncology service in southern Brazil with adolescents and young people from rural areas undergoing cancer treatment, through semi-structured, audio-recorded interviews, from April 2021 to September 2022, taking place in five phases, with data analysis carried out in light of Reflexive Inductive Thematic Analysis. RESULTS: Eleven adolescents and four young people participated in the study, the majority of whom were male, single, with a family income of up to three minimum wages and a diagnosis of Acute Lymphoblastic Leukemia. The vulnerable situations of adolescents and young people in rural areas undergoing cancer treatment involve challenges such as the emotional impact of the diagnosis, loss of contact with friends, side effects of chemotherapy, dietary restrictions, access, and travel to undergo treatment. CONCLUSION: Adolescents and young people undergoing cancer treatment face situations of vulnerability related to the disease, limited access to adequate health care, and social and emotional difficulties.