Since difficulty in defining available Cu and Mo in soils has been encountered and information on the nature of tne occurrence of these elements in soils is far from complete, it seemed desirable to study their exchangeable properties. Four different reagents, 0.2 M ammonium oxalate (pH 3.0), 0.1 N HCl, 0.1 N HCl, 0.1 N NaOn, and 2% citric acid solution were used as extractants for exchangeable Cu and Mo on some of the podzol soils of eastern Canada. Ammonium oxalate gave maximum displacement of both elements. HCl proved very inefficient for Mo, while citric acid was poorest for Cu. A comparison of the effect on both elements of removing organic matter ("indirect" extraction) with "direct" extraction was also made. A 16-hour extraction period with continuous shaking was necessary for maximum release of both elements by using "indirect" extraction. Further release from an extended extraction period gave negligible amounts. Because of the above-mentioned results, 0.2 M ammonium oxalate (pH 3.0) was considered to be the best reagent for the determination of exchangeable Cu and Mo. Further, this extractant is easy to prepare, has sufficient buffering capacity to prevent any material change in the pH of the soil extract, and forms stable complexes with Cu as well as Mo.