This study focused on Pb isotope ratios of sediments in areas around an abandoned mine to determine if the ratios can be used as a source tracer. For pretreatment, sediment samples were dissolved with mixed acids, and a multi-collector inductively coupled plasma mass spectrometer (MC-ICP-MS, Nu plasma II) was used to investigate the Pb isotopic composition of the samples. The measured isotope ratios were then corrected for instrumental mass fractionation by measuring the (203)Tl/(205)Tl ratio. Repeated measurements with the NIST SRM 981 reference material showed that the precision of all ratios was below 104 ppm (±2σ) for 50 ng/g. The isotope ratios ((207)Pb/(206)Pb) found were 0.85073 ± 0.0004~0.85373 ± 0.0003 for the main stream, while they were 0.83736 ± 0.0010 for the tributary and 0.84393 ± 0.0002 for the confluence. A binary mixing equation for isotope ratios showed that the contributions of mine lead to neighboring areas were up to 60%. Therefore, Pb isotope ratios can be a good source tracer for areas around abandoned mines.