Abstract: Wet oxidation of simulated organic filth by hydrogen peroxide catalysed by Fe~(2+) is investigated. The factors influencing reactions such as H_2O_2 dosage, catalyst, pH-value and so on are studied. With regard to reagent addition manner, intermittent addition is advised for the utilization of H_2O_2, pH value of the system is 1~2. To assure fast startup and going along placidly of the reaction, a third of the catalyst is mixed with the filth before the oxidation, the other two thirds are added in the reacting solution continuously during the reaction process and finished the addition half an hour before the end of the reaction. TBP/OK, HDBP/OK and interphase crud can be decomposed effectively by (H_2O_2). Finally, trivariant normal experiments are employed for determination of the optimal conditions. When the dosage of cruds is 2.00 g, the optimal conditions are pH=1, (10 mL )H_2O_2, (10 mL) (0.1mol/L) Fe~(2+). The element analysis and infrared spectroscopic analysis shows that the main component of the (residual) from the reaction is phosphate.