An observation by micro‐Auger electron spectroscopy has been made of the tin whisker grown on electroplated tin films. Direct experimental evidence has been obtained for the existence of zinc and oxygen impurities on tin whiskers as well as on the electroplated film surfaces when a brass or zinc‐coated metal is used as a substrate. The localization of these impurities on these surfaces may be related to the growth mechanism of tin whiskers or to the driving force by lowering the surface energy.