Adolescent and young adult (AYA) with cancer are at risk for developing sexual and reproductive problems; therefore, they have special needs. AYA with cancer treated in both pediatric and adult wards are a minority in Japan; thus, accumulating experience for supporting this unique patient population is difficult for nurses. Hence, this study aimed to clarify nurses’ perceptions on support for sexual and reproductive issues among AYA with cancer. A questionnaire survey was administered to nurses at designated cancer hospitals across Japan who had been working for at least 1 year in a department involved in the treatment or follow-up of patients aged 15-39 years. Nurses were asked regarding their perceptions on support for sexual and reproductive issues faced by AYA with cancer. A total of 865 nurses responded to this survey; nurses affiliated with adult departments, those with more experience in cancer nursing, those affiliated with cancer-related academic and professional societies, and certified nurse specialists or certified nurses significantly recognized insufficient support for sexual and reproductive issues. However, nurses were hesitant and found it difficult to intervene in such issues. Nurses recognized the importance of providing support for sexual and reproductive issues but faced difficulties in addressing them. They need to discuss these issues and improve the care provided to AYA with cancer.