A laboratory experiment was conducted to study the characteristics of leaching of Cr, Cu and As from chromated copper arsenate (CCA)-treated wood. The wood species tested was hemlock spruce (10 ㎝ × 10 ㎝ × 10 ㎝ cube). The leaching experiment was conducted over 60 days using I L of leachants whose pHs were adjusted to 2.0, 3.7, and 5.6, respectively with nitric acid, and also using lake water, according to the OECD guideline. Each leachate was analyzed for Cr and Cu using flame-AAS, and for As using vapor generation-AAS. Three metals were leached at the highest levels at pH 2.0 but almost at similar levels at the other conditions. Cumulative quantities over 60 days of a leaching period were in order As>Cu>Cr. As was predicted to leach with an increase in flux over a 10 year period, while Cr and Cu fluxes were predicted to decrease with time. This result suggests that arsenic can pose a health risk to humans over a long period of time, when CCA-treated wood is used for building facilities (e.g., playgrounds, residential purposes, etc.) with which humans frequently contact.