The present invention relates to a method for producing a high-concentration collagen for using as a medical material. After washing tissues of a mammal, the washed tissues of the mammal are grinded and deposited in ethyl alcohol, and an enzyme is treated by putting phosphoric acid in purified water, and then putting pepsin therein and stirring and reacting same, and collagen is coagulated by means of adding sodium chloride to the enzyme-treated collagen and stirring same, and the coagulated collagen is dissolved using purified water and then filtered using a filter, and pepsin, low-molecular materials, and sodium chloride in the solution are removed by using a tangential flow filtration device, and the collagen is concentrated. The concentrated collagen is sterilized and filtered, and the collagen is coagulated by using a neutralization reaction tank and a pH solution, and uncoagulated solution is removed, and then the collagen is concentrated, and the concentrated collagen is concentrated by using a centrifuge, and the concentrated collagen is put in a mixer and then stirred, and thus a high-concentration collagen is produced and used as a medical material.
