To utilize the large number of leachate resources generated in the process of cyanide tailings leaching by ferrous oxalate,based on the analysis of Fe3＋ and C2O42- forms and distributions in Fe3＋-H2C2O4-H2O system and its potential-pH figure,photocatalysis was proposed to treat the leachate for preparing ferrous oxalate and rege-neration of  C2O42- .Under the static and magnetic agitation conditions,the C2O42-  oxidation rate,iron precipitation rate,and the morphology and crystal form of ferrous oxalate were preliminarily studied.Results show that compared with the static photocatalysis,the magnetic stirring can shorten the photocatalysis time,strengthen the photocatalysis effect and reduce the particle size of β-FeC2O4·2H2O,but it destroys the morphology and increases the oxidation rate of  C2O42- ,which is not good for its regeneration.Photocatalytic conditions can be determined according to the specific performance of ferrous oxalate.A pollution-free photocatalysis is used for the recovery of iron from the leachate and regenerating C2O42- ,which realizes the recycling of leachate.At the same time,a new process of preparing FeC2O4 from the iron oxalate complex as the iron source is developed.