The authors analyzed ancient Chinese, Japanese and Korean coins for thirteen elements in order to study the relation between the chemical compositions and archaeological significance. Seven elements (copper, lead, zinc, tin, iron, nickel, and manganese) were determined by inductively couple plasma emission spectrometry and six elements (arsenic, antimony, cobalt, gold, silver, and selenium) by instrumental neutron activation analysis. Bronze coins contained copper, lead and tin as major constituents approximately in the ratio 7:2:1. Trace elements were classified into two groups according to the concentration. The trace elements in lower concentrations (nickel, silver, etc. ) showed the normal distribution over the logarithmic concentration and were attributed to contamination from natural materials. The cluster analysis based on 13 elements could not recognize each coin, but classified the coins into five groups. Coins from Sung Dynasty became lower in grade as they were cast later in that period. The ratio of major constituent contents was copper to zinc 7:2 in Japanese brass coins and 1:1 in Chinese coins. As compared with bronze coins, brass coins contained more arsenic, antimony and iron but less silver and selenium. See also AATA 20-2192.