Polylactide is an important part of biodegradable material. Among the numerous synthesis methods “immortal polymerization” has aroused researchers” attention in just recent years. This review introduces the latest developments of lactide “immortal polymerization” catalytic systems. in which monobasic, polyhydric or functionalized alcohol act as chain transfer agents with rare earth metal as catalysts. This review also presents using “immortal polymerization” to synthesize polylactide and its copolymer with topological structure.