To evaluate the performance of a real-time continuous glucose monitor (CGM) in individuals with diabetes on peritoneal dialysis (PD). Thirty participants with type 2 diabetes on continuous ambulatory PD wore a Guardian Sensor 3 on the upper arm paired with Guardian Connect for 14 days. We compared CGM readings against Yellow Springs Instrument (YSI) venous glucose during an 8-h in-clinic session with glucose challenge. The mean absolute relative difference (MARD) was 10.4% (95% CI 9.6, 11.7) from 941 CGM-YSI matched pairs; 81.3% of readings were within %15/15 of YSI values in the full glycemic range. Consensus error grid analysis showed 99.9% of sensor values in zones A and B. There were no correlations between pH, uremia, hydration status, and MARD. We showed satisfactory performance of a real-time CGM sensor in PD patients with diabetes, supporting future use to facilitate treatment decisions.