Abstract: 1.A brief summary of the literature on the methods of purification and preparation of penicillin salts is given.The methods are compared and technical requirements for industrial-scale production are discussed. 2.Potassium acetate saturated in ethyl alcohol is proposed(first in 1949) as crystallizing reactant for the preparation of the potassium salt of penicillin.It was found to give 70% yield of the crystalline salt in direct precipitation from organic solvent extracts and 90% yield when azeotropic distillation was employed. 3.Experiments on the method are given in detail and the conditions for its application in industry are indicated.