Abstract: Traditional network file system can not reach the achievement of high-performance computing systems，but parallel network file system-PNFS can resolve the problems of traditional file systems about scalability，availability and performance.First，the paper introduces the architecture of PNFS.PNFS enables the separation of the metadata server and the storage server to eliminate the I/O bottleneck caused by the centralized architecture.Second，the test of PNFS is done，and then the test results are compared with NFS in the same environment.Both theoretic analysis and the test results show that PNFS provides the ability to access file data parallel，it has a relatively high I/O read/write bandwidth with low latency，and it can get the linear increases on the I/O bandwidth with the increasing number of storage servers.So PNFS can meet the I/O requirements of HPC.