Background: Cancer disease is considered one of the basic health problems in the world, which threatens the health of human life. It causes numerous personal, family and social damages in physical, psychological, and social dimensions. Objectives: The present study aimed at investigating health literacy and cognitive dysfunction on the quality of life of cancer survivors to make better decisions for the daily functioning, quality of life, and work capacity of cancer survivors so that their lives can be spent with more peace and less stress. Methods: With a descriptive correlational design, 350 cancer survivors of the Cancer Research Center of Shahid Beheshti University of Medical Sciences (Shohaday Tajrish Hospital) from September to November 2021, who had been treated for at least one year, volunteered online and in person. Cognitive failure (Broadbent et al., 1982), cancer health literacy test (Dumenci et al., 2014), and quality of life of adults surviving cancer (Avis et al, 2005). Results: Pearson correlation showed a negative relationship between cognitive dysfunction and quality of life; so, path analysis showed that 25% of the quality of life is explained by cognitive dysfunction, but cancer health literacy was not correlated with the quality of life of cancer survivors. Conclusions: According to the findings, the optimization of cognitive functions after treatment was emphasized to increase the quality of life of cancer survivors.