Background: This systematic review aimed to investigate resilience and its related factors in caregivers of adult patients with cancer. Materials and methods: A systematic search of online electronic databases including Scopus, PubMed, Web of Science, Iranmedex, and Scientific Information Database (SID) was performed using keywords extracted from Medical Subject Headings such as “Psychological Resilience”, “Caregiver”, and “Cancer” from the earliest to 6 June 2023. The quality of the studies included in this review was evaluated using the appraisal tool for cross-sectional studies (AXIS tool). Results: A total of 2735 caregivers of cancer patients participated in 15 studies. The majority of the studies found that caregivers of cancer patients had high levels of resilience. Factors related to the resilience of cancer patients’ caregivers included caregivers’ social support, caregivers’ quality of life, patients’ resilience, caregivers’ family function, patients’ performance, caregivers’ age, caregivers’ health status, caregivers’ self-esteem, caregivers post-traumatic growth, caregivers religious, caregivers hope, caregivers positive affect, patients age, patients social support, patients resilience support, patients quality of life, caregivers’ anxiety, caregivers’ depression, caregivers’ burden, caregivers level of education, caregivers financial problem, caregivers memory, caregivers negative affect, caregivers post-traumatic stress disorder, maternal distress, and patients post-traumatic stress disorder. Conclusion: Therefore, healthcare administrators and policymakers can enhance the resilience of caregivers and the quality of care they provide by instituting ongoing training initiatives focused on evaluating mental well-being and implementing coping strategies for managing stress and depression.