Objectives: Evidence regarding the difference in survival outcomes between kidney transplant and dialysis in cancer patients is lacking. Methods: We conducted a retrospective observation study using the Inner Mongolia Regional Health Information Platform. Patients underwent kidney transplant or dialysis with a preexisting cancer diagnosis during 1/1/2012-31/12/2021 were included. The primary outcome was overall mortality. The secondary outcome was cancer-specific mortality. Propensity score matchings were used. Results: Among 170 414 patients diagnosed with cancer, 1762 patients started kidney transplant or dialysis. There were 5.45% (n=96) patients using kidney transplants, and 94.55% (n=1666) dialysis. Female was less likely to commence kidney transplant (OR=0.381, 95%CI:0.237-0.602). During a median follow-up of 5.73 years, 438 (24.86%) deaths were recorded. The overall mortality (12.50% vs. 25.57%, p=0.004) and cancer-specific mortality (6.25% vs. 14.89%, p=0.019) were lower in the kidney transplant group. In propensity score matched cohort, kidney transplant was associated with decreased overall mortality (HR=0.366, 95%CI:0.186-0.720) and cancer-specific mortality (HR=0.330, 95%CI:0.128-0.853). The difference in annual medical costs between the transplant and dialysis was not statistically significant ($10 016.37 vs. $10 977.18, p=0.982). Conclusions: Our findings underscoring the urgent need to promote kidney transplants, address donor shortages, and ensure sex-equitable transplant access for kidney failure patients.