A D.C. arc carrier distillation atomic emission spectrometry based analytical method was developed for the determination of 20 metallic impurities at the trace level. A suitable composition of the carrier gas (5% AgCl) was optimized to sweep away the trace metallic constituents into the arc, leaving the refractory nuclear material matrix inside the electrode to avoid spectral interference from the emission-rich major matrix. The method was optimized by using a suitable choice of interference-free analytical lines for the trace elements with desired analytical performance, including detection limts, linear dynamic range, and sensitivity. The method was validated using synthetic samples analyzed against U3O8 standards as well as 30% PuO2 mixed oxide standards. Using the optimized methods, actual U-Pu-Zr alloy samples were analyzed, and the method was found to be satisfactory.