Precipitation behaviors of metallic impurities in CZ-silicon single crystals were investigated with a transmission electron microscope equipped with an energy dispersive x-ray spectrometer. Results show bulk precipitates only for Au, Cu, Ni. Effect of near-surface denudation of SiOx micro-precipitates to suppress the metal precipitation in the denuded zone was explicit both Cu and Ni cases. But Au precipitated uniformly. Fe and In precipitates were localized in the near-surface region. The other metals (Cr, Mo, Al, Te, Ta and Pb) remained on the wafer surface and did not seem to segregate to the deliberately introduced defects (stacking faults, dislocation and SiOx) nearby the deposit. Among those metals impurity precipitation on stacking faults and dislocations was observed significantly only in Cu contaminated wafer. Most of metals seemed to be less mobile under oxidizing atmosphere by oxygen trapping of the metal at the wafer surface.