The literature on the solubility of the sparingly soluble inorganic salts of zinc and cadmium in water and in aqueous electrolyte solutions has been reviewed. The solubility data have been compiled and evaluated. Recommended or tentative values of the solubilities and the solubility products have been given when warranted. Auxiliary thermodynamic and crystallographic data useful in the interpretation of solubility data are given. For the many zinc and cadmium substances for which only limited solubility, data are available, unevaluated values are given in an annotated bibliography with emphasis on solubility data published since 1950.