The invention discloses an automatic opening, adding and dissolving liquid supply system for upright soft bag powder. The liquid supply system comprises a temporary storage assembly, a discharging assembly, a transferring assembly, a bag opening assembly, a liquid preparation assembly, a recycling assembly and a liquid storage assembly. Powder bags sequentially pass through the temporary storage assembly, the discharging assembly, the transferring assembly, the bag opening assembly, the liquid preparation assembly, the recycling assembly and the liquid storage assembly to complete the actionsof powder transportation, temporary storage, transferring, clamping, bag opening, discharging, liquid preparation, liquid storage and bag body recycling, so that the whole process of the liquid supplysystem is automatic, and only manual participation is needed during bag placing; the automation level of equipment is effectively improved, dependence on personnel is reduced, liquid preparation andimmediate preparation can be directly carried out after a powder bag package is opened, the quality of liquid medicine is effectively guaranteed, meanwhile, powder can be prevented from being polluted, the equipment is prevented from being corroded by the powder, the maintenance cost of the equipment is reduced, the service life of the equipment is effectively prolonged, and good application prospects are realized.