Abstract This paper presents a distributed storage system which is built by lots of low-cost nodes. Low-cost node is divided into two parts: metadata nodes and storage nodes. The storage system will use a group of low-cost metadata nodes instead of the Google File System's (GFS's) single master server machine. These metadata nodes are linked by high-speed and high-density local peer-to-peer (P2P) network. We also designed the method organized metadata in the metadata cluster. The storage nodes are also linked by high-speed local P2P network. Metadata cluster and storage cluster are linked through high-speed reliable network. User files are organized into a tree structure by using a virtual storage component called “unit”. Storage system is built on the top of every node's operating system. This paper also gives the specific way of file addressing.