The invention relates to a more-stable carbetocin acetate injection. The preparation consists of carbetocin acetate, an isoosmotic adjusting agent, a pH value regulating agent, an antioxidant, a local analgetic and a solvent, wherein the addition of the antioxidant can improve the stability of the preparation, and the addition of the local analgetic can relieve pains of a patient but does not affect the basic remedy. The process for preparing the preparation mainly comprises the following steps: weighing, dissolving, adsorbing a heat source by activated carbon, filtering, filtering by a terminal, subpackaging and sealing. The preparation is used for preventing and treating insufficient uterus tension and postpartum hemorrhage. The preparation has stable quality and an exact curative effect, and can be accepted by patients.