Sunitinib is a tyrosine kinase inhibitor of both platelet derived growth factor (PDGF) and vascular endothelial growth factor (VEGF) receptors. It has shown great efficacy in metastatic and cytokine refractory advanced renal cell carcinoma. The focus of this article is on its dermatological effect in combination with radiotherapy. In this case report, the patient concurrently received sunitinib and radiotherapy developed severe skin reaction in irradiation field. This type of skin reaction has never been reported in the literature. We hypothesized that the skin reaction in radiation field may be precipitated by sunitinib. Further observation may be warranted while sunitinib is prescribed to RCC patients receiving radiotherapy.