OBJECTIVE： To prepare Polygala fallax rapidly disintegrating oral tablets and investigate its in vitro dissolution. METHODS： The rapidly disintegrating tablets was prepared by direct powder compression method. Using disintegration time as index， the ratio of stuffing bulking agent mannitol to disintegrating agent microcrystalline cellulose， the amount of drug extract， the amount of lubricant magnesium stearate and other influential factors were investigated by single factor test and orthogonal test. The drug dissolution effect of prepared tablet （using senegenin as substance control） was evaluated by in vitro dissolution test （using water as dissolution medium， paddle method）. RESULTS： The optimal formulation was that the amount of drug extract was 15％； the ratio of mannitol to microcrystalline cellulose was 1.5 ∶ 1； the amount of magnesium stearate was 1.0％. The disintegration time of prepared tablet was （31±4） s； tablet hardness was （3.4±0.2） kg； tablet friability was （0.23±0.07）％ （RSD＜0.11％， n＝3）. Accumulative dissolution rate of total saponins was more than 90％ within 5 min. The dissolution parameters T50 was equal to 0.84 min and Td was equal to 1.77 min. CONCLUSIONS： Polygala fallax rapidly disintegrating oral tablets will dissolve quickly and disintegrate rapidly in aqueous solution.