PDLLA/CHI/β-TCP/NGF composite films were prepared by a solvent evaporation method.The degradation characteristics of the poly (d, l-lactide) composite films were studied in vitro and in vivo.The acidity produced by poly (d, l-lactide) materials was not obvious. Adding chitosan and β-TCP can relieve the acidity problem and improve strength performance of films. The NGF has influences on the degradation characteristics of films. It is verified that PDLLA/CHI/β-TCP/NGF composite films prepared by solvent evaporation method have excellent degradation characteristics. It can be used as a perfect biomaterial for repairing nerve injuries.