[en] The determination of uranium and thorium in monazite samples by Inductively Coupled Plasma Atomic Emission Spectrophotometry (ICP-AES) technique were done. The spectra of rare earth elements, thorium and iron interfered those of uranium at 6 wavelengths. The spectra of thorium were interfered from those of rare earth elements at 374.118 and 401.913 nm. wavelengths. The increasing of sulfuric acid and perchloric acid concentrations decreased the emission intensity of uranium and thorium. Hence, the quantity of sulfuric and perchloric acid in the standard and the sample solutions were equally added. Sulfuric acid was the best of all mineral acids to open the monazite mineral. The 7 ml of sulfuric acid was selected for 1 gram of monazite. Rare earth and thorium elements were separated from uranium by the precipitation with ammonium oxalate. The 30 mg of ammonium oxalate is suitable for precipitation of 1 ml of 0.012 g rare earth and thorium weights. The precision and accuracy of the method were verified by using the known concentration of IGS-36 and NBS-7A reference standard materials. The uranium and thorium values obtained in ten monazite sample were found to be in good agreement with those obtained by INAA method