A microwave digestion procedure was developed for the determination of trace Zn, Mn, Cd and Pb in aloe-leaf cuticle and aloe-leaf gelatin, using the obturated vessel microwave digestion system with a pressure controlling part, and the amounts of these trace metallic elements were determined by atomic absorption spectrometry after microwave digestion. The effects of the composition of digestion solution, the ratio of the sample to digestion solution, and the digestion time were studied. It is satisfactory to apply the microwave digestion procedure to the determination of Zn, Mn, Cd and Pb under the optimized condition with the recovery of 95.0% to 110.0% and RSD of 0.3% to 6.2%. The results show that this method is rapid and simple with low environmental contamination and complete digestion of the sample.