The invention discloses a preparation method of an ethionamide tablet, and the preparation method comprises the following steps: (1) weighing the following raw materials by weight: 250 parts of ethionamide; 40-55 parts of a filler; 15-25 parts of a disintegrating agent; 10-15 parts of a binder; 6.25 parts of a flow aid and 1 part of a lubricant; and (2) mixing the ethionamide and the flow aid, crushing, sieving by a 100 mesh standard sieve, adding the filler, the disintegrating agent and the binder for mixing, adding an auxiliary solvent with an amount being 6% of the total amount of the formula for wet granulation, baking at the temperature of 60DEG C for 20min, trimming granules by a 16-20 mesh standard sieve, adding the lubricant, and tabletting to obtain the ethionamide tablet. By using the preparation method of the invention, crushing and sieving of ethionamide raw material drug is convenient, the prepared tablet is small in tablet weight difference, and the quality of the drug is well controlled.