This method is for determining trace (mass-ppm) concentrations of aluminum, silicon and silver in acetic acid by Inductively Coupled Plasma-Optical Emission Spectrometry (ICP-OES). The lower limits of detection for aluminum, silicon, and silver are 0.1 mass-ppm, 1 mass-ppm, and 0.01 mass-ppm, respectively. The upper range of determination is approximately 100 mass-ppm. The method is also applicable, but has not been verified, for the determination of other metals.