Infertility is a frequent late effect of cancer treatment that significantly affects cancer survivors' quality of life. In recent years, with advances in oncofertility, the number of children with cancer receiving fertility preservation therapy has increased. However, specific challenges exist in pediatric cancer patients. First, fertility preservation therapy for children with cancer relies significantly on their age and sex. Ovarian tissue cryopreservation is possible until puberty in females, and after menarche, the ovarian tissues and oocytes can be preserved. Sperm cryopreservation is a well-established technique for male adolescents. However, prepubertal boys are deprived of such methods. Second, ethical considerations are important when providing information about treatment-related infertility risk and fertility preservation to children. Third, because most childhood cancer survivors cannot remember their cancer treatment, information should be provided repeatedly, according to the patient's growth and level of understanding. Currently, the provision of information to patients with childhood cancer is insufficient. Therefore, the PanCareLIFE Consortium and the International Late Effects of Childhood Cancer Guideline Harmonization Group have developed clinical practice guidelines for ongoing communication regarding treatment-related infertility risk and fertility preservation in patients with a history of childhood, adolescence, or young adult cancer. In April 2021, Japan implemented a public subsidy system to partially fund the expenses related to oncofertility. In the future, multidisciplinary healthcare providers should collaborate to provide appropriate information and support to the patients and their families.