Purpose: Physical activity (PA) has been suggested to help increase the survival of individuals with cancer. The objective of this review was to systematically evaluate and summarize the available evidence investigating the effect of PA on the survival of individuals with cancer. Methods: Electronic databases (CINAHL, EMBASE, and MEDLINE) were systematically searched for randomized controlled trials and cohort studies. Selected studies were assessed by two independent investigators for methodological quality, using the PEDro scale. Results: Ten prospective cohort studies met the inclusion criteria. Quality-assessment scores averaged 5/10 on the PEDro scale, with two articles obtaining a score of 6/10. The majority of studies found that individuals participating in higher levels of physical activity had a reduced risk of cancer-related mortality. This trend was observed specifically for breast, colon, and colorectal cancers. On average, it appears that engaging in higher levels of metabolic equivalent hours per week may help to improve survival rates among individuals diagnosed with cancer. Conclusion: Patients diagnosed with cancer demonstrated a trend toward increased survival with greater levels of PA. However, because only prospective cohort studies were included in the study, the conclusions drawn should be regarded with caution.