Several studies show that self-perception of aging (SPA) is a significant predictor of mental and physical health. In this study, we analyze the effect of SPA on mortality in the specific context of geriatric oncology.The sample constituted of 140 individuals aged 65 years and older suffering from a recent nonmetastatic cancer (breast, lung, gynecological, or hematological), followed up to 6 years. We used Cox proportional hazards model to assess the effect of SPA at baseline on mortality. It was adjusted for age, gender, educational and cognitive level, oncological information (the site and kind of cancer), number of comorbidities, and physical and mental health at baseline.Patients were aged 73 years at diagnosis and were more often women (85.7%). Individuals with more negative SPA were 3.62 times more likely to die than those with a more positive SPA, with control of gender, age, education and cognitive level, mental and physical health, the category (breast, lung, gynecological, or hematological), and kind (initial or recurrence) of cancer.These findings suggest that SPA influence the mortality of older people in the particular context of oncology. Therefore, the need to change our attitudes toward aging and older people implied indirectly by these results is discussed.