The digital fault recorder uses a PowerPC8270 based hardware platform and an embedded Linux operation system based software platform. The device receives the sampling date send by the merging unit according to IEC 61850-9-1 standard and GOOSE data send by the protection control unit according to IEC 61850-8-1 standard. It realizes digital data and sampling data synchronization on GPS locked and lost according to synchronized merging strategy. Thus， the correct GPS time is extracted and fault recorder file is formed at the end. The proposed recorder satisfies the new requirements of fault recorder in digitalized substations.