Tacrolimus, an immunosuppressive drug used post organ transplant to mitigate rejection risk, often induces significant blood glucose fluctuations, contributing to posttransplanthyperglycemia and diabetes. This study aimed to assess RBS levels pre and post transplantation (days 1 and 90) and tacrolimus levels in diabetic patients. Renal transplant recipients (n=93, age >18 years) were included, excluding hemolyzed samples, pregnancy, and immunocompromised conditions. Statistical analysis (SPSS v20) revealed a significant increase in mean RBS levels from baseline (128.55±35.92 mg/dl) to day 1 (200.66±68.84 mg/dl) and a modest rise at day 90 (132.11±50.84 mg/dl). Among diabetic patients (14%), tacrolimus trough levels were significantly higher on day 1 (8.89 ng/ml) compared to nondiabetics (5.75 ng/ml), with sustained elevation seen at day 90 (8.4 ng/ml vs. 7.53 ng/ml). These findings underscore the association between tacrolimus levels and diabetes risk post transplantation.