The invention relates to a puerarin sodium phosphate injection and a preparation method thereof. The preparation consists of sodium puerarin phosphate, antiseptic, isotonic regulator, pH regulator, antioxidant, local analgesic and water for injection. The addition of antioxidants can improve the stability of the preparation, and the addition of local analgesics can reduce the pain of patients without affecting the main drug. The preparation process of the preparation mainly includes weighing, dissolving, pyrogen adsorption by activated carbon, filtering, constant volume, terminal filtering, sub-packaging and sealing and capping. The preparation is used for auxiliary treatment of coronary heart disease, angina pectoris, myocardial infarction, retinal artery and vein occlusion, sudden deafness and ischemic cerebrovascular disease, etc. The preparation has stable quality, definite curative effect and is favorable for patients to accept.