The vaccine against chlamydous infections consists of an inactivated suspension of cells of yolk sacks of chicken embryos infected with a chlamydous infectant in a physiological solution or a phosphate buffer solution and an adjuvant; as the latter use is made of an aqueous solution of a mixture of tris-hydroxymethylaminomethane and tetramethylethylene diamine, an aqueous solution of a mixture of acrylamide and methylbisacrylamide, an aqueous solution of ammonium persulphate and an aqueous solution of glutaric aldehyde the components being present in the following proportions, ml______________________________________ antigenous liquid of an inactivated suspen- sion of cells of yolk sacks of chicken embryos infected with a chlamydous infectant 8-10 aqueous solution of a mixture of tris- hydroxymethylaminomethane and tetraethylene- diamine in a weight ratio of 15-16:1 respectively 1-2 aqueous solution of a mixture of acrylamide and methylbisacrylamide in a weight ratio of 37-38:1 respectively 3-4 1.4% aqueous solution of ammonium persulphate 1-2 25% aqueous solution of glutaric aldehyde 0.026-0.028 physiological solution or phosphate buffer solution - in an amount equal to the total amount of the above-mentioned components. ______________________________________ A method for prophylaxis of chlamydous infections of farm animals comprising administration of the above-specified vaccine to animals hypodermally or intramuscularly once in doses: for cattle--5 ml, for small cattle--1-2 ml.