The photocatalytic oxidation of free cyanides in aqueous suspensions containing polycrystalline TiO2 (anatase) powders irradiated in the near-UV region has been investigated. The rate of cyanide photooxidation has been studied by varying the following operative parameters : (i) initial cyanide concentration; (ii) catalyst concentration; (iii) initial pH; (iv) power of irradiation; and (v) chloride ion concentration in the reacting mixture. Under the used experimental conditions the photoreaction proceeded at a measurable rate until the complete disappearance of cyanides. The kinetics of cyanide photooxidation is affected by the catalyst concentration, the chloride ion concentration, and the power of irradiation while it is independent of the initial cyanide concentration and the pH. The detrimental effect of chloride ions on cyanide photooxidation rate is not determined by a competition mechanism of chloride ions with cyanide ions or oxygen molecules for adsorption on active sites. Chloride ions affect the photoreaction rate by lowering the concentration of dissolved oxygen to values for which oxygen may become a rate limiting reactant. The Langmuir-Hinshelwood kinetic model well fits all the photoreactivity results. The reaction pathway was also investigated; cyanate, nitrate, and carbonate were found to be the main oxidation products. A mass balance on nitrogen was also successfully carried out. Specific experiments were carried out in a particular setup for measuring both the photon flow absorbed by the reacting suspension and the cyanide photoreaction rate; for these particular conditions the quantum yield value was calculated.