Acute rejection is the most critical post-kidney transplant complication occurring in approximately, 30-50 % of recipients. In this study we analyzed the panel reactive antibodies (PRA) as an immunological indicator that may help in predicting acute rejection before the operation. Eighty pre- transplant patients' sera were collected from the Immunology Laboratory Hamad Al-Essa Kidney and Organ Transplant Center at Sabah Hospital in Kuwait, and analyzed in the Immunology laboratories of the Arabian Gulf University and the Salmaniya Medical Complex in Bahrain. The study populations were divided according to biopsy findings into forty acute rejection group (AR), and forty no rejection (No-R) group. Both groups were analyzed for PRA by a screening Flow cytometry test and class I and II specific Flow-PRA, using Flow-PRA beads. Among the 40 patients in AR group test, only 4 had positive Flow-PRA screening, further analysis by Flow-PRA specific class I and II, showed that they had anti-HLA antibodies against their donor's HLA. In conclusion, The data suggest that pre-transplant PRA is a useful immunological indicator to be used to predict acute rejection event especially if the test is used to show the anti-HLA antibodies specifity and not only the percentage.