Abstract: The wide array of applications for PLA foams, such as packaging, automobiles, and tissue engineering, were introduced. And, various PLA foaming technologies, such as solidstate foaming, extrusion foaming, injection foaming, and other foaming methods, as well as their foaming mechanism, were also listed. Some advanced and effective modification methods, including chain branching of PLA molecular, blending with other polymers, and filling with micro-/nanosize particles, were dealt with. And, the cellular structures induced by the modifications of PLA were also introduced.

Key words: poly(lactic acid), foam, biodegradable, foaming, supercritical carbon dioxide