The invention discloses a preparation method of a collagen film for guided tissue regeneration. The method comprises the following steps of dissolving collagen in an acid solution, adjusting a pH (potential of
hydrogen) value of an obtained solution to 5-9, continuing to conduct rapid shearing and stirring on the obtained solution, obtaining a collagen
emulsion, centrifuging the obtained collagen
emulsion, collecting the collagen film on the solution, allowing the obtained collagen film to be subjected to mold forming, freeze-
drying, using a physical or / and chemical method for crosslinking, and obtaining the collagen film for the guided tissue regeneration. The obtained collagen film has excellent
mechanical property and
controlled degradation property, has a gradient pore structure, is suitable for transmission of
nutrient substances and adsorption and multiplication of cells, and can better guide repair of defect tissues; the preparation technology is simple; the cost is lower; and the large-scale production is facilitated.