The present invention provides a pharmaceutical composition containing steroidal saponins. The pharmaceutical composition comprises 5˜25 parts by weight of furostanal saponins represented by general formula A or general formula B and 1˜10 parts by weight of spirostanol saponin represented by general formula C. The present invention further provides a method for preparing the pharmaceutical composition. After determination of the three steroidal saponin components in the pharmaceutical composition of the present invention, it is proved that it has high stability and liability in its therapeutic effect. Meanwhile, the method to identify the three steroidal saponins is provided with reliable controllability. Besides, with its daily dosage of 300˜600 mg, which is less dosage, the drug of this invention provides a new choice in clinics.