Kaposi’s sarcoma (KS) is a relatively common malignancy after kidney transplantation. We conducted a retrospective analysis to identify all cases of Kaposi's sarcoma complicating kidney transplantation in 8715 recipients at the 6 transplant centers (Baqiyatallah, Labbafi-Nejad, Urmia, Chamran, Milad and Yaser hospitals) between 1984 and 2008. Kaposi's sarcoma developed in 47 (0.5%) recipients; one patient had lymphoproliferative disorder and another with renal cell carcinoma as well. The variables studied were patient age, gender, type of transplant, immuno­suppression, simultaneous neoplastic or infectious problems, treatment received, progression of KS in individual patients, renal allograft function, and rejection episodes, the clinical presentation of Kaposi's sarcoma, follow-up and outcome. The affected patients were 27 males and 20 females. There was no relationship between developing of Kaposi's sarcoma and gender. The mean age of the patients at the time of diagnosing KS was 49 (range from 21 to 71) years. KS was more occurred in older age at transplantation when compared to patients without KS (P = 0.000). The time interval between transplantation and diagnosis of KS ranged between 2 and 143 months with a mean period of 29 months. Skin involvement was universal; mucocutaneous lesions occurred in 40 patients (85%) and visceral disease was noted in 7 patients. Therapy for Kaposi's sarcoma consisted of immunosuppression withdrawal (n = 18), decrease in immunosuppression (n = 27), changing to sirolimus (n=2), chemotherapy (n = 6), radiotherapy (n = 2), conventional surgical excision of the lesions (n = 1), and 6 patient died before receiving complete treatment. Renal function was preserved when immunosuppression was reduced instead of withdrawn (P=0.009). The overall mortality in this series of patients was 19% (9 of 47 patients) and it was higher in patients with visceral involvement compared to those had mucocutaneous lesions (P=0.02). In conclusion, our study shows that simple reduction or cessation of immunosuppression may result in partial or complete remission of the disease.