Urban rainfall runoff pollution for a settlement area of Adana city was investigated experimentally. For this purpose, runoff waters were sampled on 16 different rain periods between October 1999 and May 2000 in Mahfesigmaz, which is in Northwest Adana Upper City Development Region. Various parameters such as pH, EC, SS, VSS, COD, BOD5, TP, TKN, Fe, Zn, Pb, Cd and Ni were analyzed for characterization of rainfall runoff waters. It was seen that concentrations of these parameters were rather high when comparing with related water quality and domestic wastewater discharge standards. It was determined that the rainfall runoff waters collected from the study area contain high pollutant concentrations and shouldn't be discharged, directly to the receiving water bodies. Treatment requirement of the highly polluted urban runoff waters conveyed separate systems creates an additional cost for the existing units. Therefore, combined sewer systems are the convenient system for the conveyance of urban stormwater for Adana city and the similar settlement areas.