Cancer poses numerous challenges for the elderly and affects various aspects of their lives, including economic, family, psychological, social, and physical well-being. This study aimed to investigate the supportive care needs of the elderly with cancer. In this descriptive-analytical research, 248 elderly individuals (144 men and 104 women) with a mean age of 67.17 ± 6.94 years, who were diagnosed with cancer, were selected from the Seirei Mikatahara General Hospital, Japan, in 2023 using a non-probability and convenience method. Data were collected through a validated and reliable supportive care needs survey designed for cancer patients, which assesses five key domains: daily functioning, physical needs, health system support, sexual health, and mental health care. The results showed that there was a statistically significant relationship between gender and several supportive care domains, including physical functioning, daily performance, sexual health support, and health system information (P < 0.05). Elderly women needed more help in daily and physical functioning, while elderly men needed more support in the areas of care, sexual health, health system, and information. The study concluded that the unmet needs of elderly cancer patients are particularly high in the areas of physical and daily functioning.