The invention belongs to the technical field of natural antibacterial medicines, and particularly relates to an application of a pregnane alkaloids compound extracted and separated from pachysandra terminalis in preparation of antibacterial medicines. The molecular formula of the pregnane alkaloids compound is C28H46N2O2, and has a chemical structural formula as shown in the specification. The pregnane alkaloids compound DSHP indicates a full-course growth inhibiting effect on drug-resistance bacteria, and shows an excellent bactericidal activity when the concentration is 50 microgram/mL. Compared with traditional antibiotics, the pregnane alkaloids compound has a remarkable protecting effect on liver, kidneys, spleen, lung and other organs of an affected mouse and cannot easily generate induced resistance.