Recebido em 7/10/09; aceito em 6/4/10; publicado na web em 9/8/10 EVALUATION OF SAMPLE PREPARATION PROCEDURES FOR AFLATOXIN ANALYSIS IN RAW PEANUT. The variability in aflatoxin B 1 concentration among peanut subsamples of 4 sample preparation procedures was evaluated. For each procedure, 18 samples were prepared involving dry comminuting/homogenization or dry roughly comminuting followed by the preparation of a aqueous slurry. Ten analytical samples were withdrawn from each sample/procedure and analyzed by thin layer chromatography. The coefficient of variation (CV%) among each set of 10 analytical samples was assumed to be associated with the sample preparation procedure. The procedure that made use of a subsample mill and preparation of a subsample slurry, showed lower variability (CV%) among the analytical subsamples.