The spatial distribution, degree of pollution and major sources of polychlorinated biphenyls (PCBs) were evaluated in surficial sediments of Ankara Creek, located in the capital of Turkey and serving as one of the tributaries in the third largest watershed in Turkey. Sediment sigma PCB concentrations analyzed on Aroclor and congener basis (seven indicator congeners) range from 5.5 to 777.6ng g1 and 3.7 to 743.3ng g1 dw as Aroclor and congener based concentrations, respectively. High concentrations of sigma PCBs were observed in the samples located at the downstream sections of the Creek, after discharge from Ankara municipal wastewater treatment plant. Using a chemical mass balance receptor model (CMB), major sources of PCBs affecting the sediments were investigated. The CMB model identified Aroclor 1254 and 1260 to be the major PCB sources affecting sediments. The potential sources for the PCBs were briefly discussed in terms of their use in various industrial applications.