Objective: Human BK virus (BKV) is a member of the polyomavirus family. In renal transplant recipients, reactivation of BKV may cause the renal-allograft dysfunction. Primary BKV infection usually occurs asymptomatically during childhood. After primer infection, BKV persists latently especially in the urogenital system. Cellular immunity plays an important role in the pathogenesis of BKV infection. The aim of this study was to determine the urinary cytokine responses in patients with BKV infection and associated levels of urinary cytokines and BK viruria.