BK virus nephropathy has emerged as an important cause of renal allograft dysfunction. Reduction in immunosuppression is the mainstay of BK virus nephropathy treatment. However, decreasing immunosuppressive medications is not sufficient for treatment of BK virus nephropathy. Therefore, there is a need for other treatment strategies such as cidofovir, leflunomide, and intravenous immunoglobulin in combination with immunosuppression reduction. Ciprofloxacin has recently been reported to have antiviral activity and decrease BK viral load in kidney transplant recipients. These findings suggest that the use of ciprofloxacin represents a valuable treatment strategy in patients with BK virus nephropathy. Here, we report on our experience with three patients who developed presumptive BK virus nephropathy after kidney transplantation, who, after 2 months of ciprofloxacin treatment, showed disappearance of BK viremia and improvement in the estimated glomerular filtration rate. Ciprofloxacin may be considered an effective treatment option for BK viremia in kidney transplant recipients.