Tissue engineering scaffolds refer to materials that can bind with living tissue cells and be implanted into the body, serving as the most fundamental framework for tissue-engineered tissues. Polyglycolic acid (PGA) and polylactic acid (PLA) are typical synthetic biodegradable polymers. Their general structural formula is [OCH2(R)CO--], where R is H for polyglycolic acid and CH3 for polylactic acid. Since both lactic acid and glycolic acid are intermediate metabolites of the tricarboxylic acid cycle, their absorption and metabolism mechanisms are well understood and they possess reliable biocompatibility and biosafety. As tissue engineering scaffold materials, PLA, PGA, and their copolymers not only have excellent biocompatibility, biodegradability, and degradability modifiability but can also induce the upregulation of certain genes. The preparation of this tissue engineering porous scaffold material By placing polylactic acid copolymer particles in a mold for hot pressing molding, then mechanically saturating the molded polylactic acid copolymer with high pressure CO2 gas at room temperature under a pressure of 3.0-30.0 MPa, while spraying polar solvents from the liquid solution inlet at the upper end of the expansion chamber; after sufficient mechanical saturation time, rapidly reducing the air pressure to atmospheric level within 1-100 seconds, the solubility of CO2 gas in the polylactic acid copolymer rapidly decreases, generating a large number of CO2 gas cavities, thus forming a porous foam structure, which becomes a three-dimensional scaffold for tissue engineering. Currently, polylactic acid scaffold materials have been widely used as scaffold materials for bone, cartilage, blood vessels, nerves, skin, and other tissues, showing their good application prospects.