Disclosed is a preparation of Pulsatilla saponin B4 for injection, comprising Pulsatilla saponin B4 and a pharmaceutically acceptable excipient. The preparation is an aqueous injection or a lyophilized powder injection, more preferably a lyophilized powder injection. Methods for preparing the Pulsatilla saponin B4 aqueous injection and the Pulsatilla saponin B4 lyophilized powder injection comprise dissolution, fluid preparation, filtration and other steps. The preparation of Pulsatilla saponin B4 for injection has a low effective dose for reversing renal injury caused by cisplatin, significantly improves the medication safety of Pulsatilla saponin B4, and is expected to provide a new option for the clinical treatment of renal injuries and renal failure.