Pb isotope ratios ₂₀₆Pb:₂₀₄PB, ₂₀₇Pb:₂₀₄Pb, ₂₀₈Pb: ₂₀₄Pb, ₂₀₇Pb:₂₀₆Pb, and <s208 >sPb:₂₀₆Pb in Japanese galena ores and archaeological bronze objects were determined by mass spectrometry using a Re single filament as a surface ionization device. Basic experimental conditions including detection limits, fractionation effects, memory effects, etc., were examined, and the accuracy of the determination was checked using a shelf standard. Archaeological bronze objects were dissolved in HNO₃ and Pb was extracted by the dithizone method. When 0.5 mug Pb was loaded on the Re filament with H₃PO₄ and silica gel as stabilizers, an ion current of 10_-13-10<s-15> s A due to Pb+ was obtained and maintained stable for several h. Relative standard deviations for the isotope ratios ₂₀₇Pb: ₂₀₆Pb and ₂₀₈Pb: ₂₀₆Pb were 0.1-0.5%. Pb isotope ratios were given for 17 Japanese galena ores and for archaeological bronze objects such as bronze bells, halberds (Yayoi period), Horyuji pagoda spire (7th century), and Northern Sung coins (11th century). A close resemblance of the isotope ratios was found between Japanese galena ores andsome Japanese bronze objects of the 7th century, suggesting the use of the former as raw materiais for the latter. See aiso 14-1279. -- AATA