保存区域网络（英文：Storage Area Network，缩写：SAN）是一种连接外置存储设备和服务器的架构。人们采用包括光纤信道技术、磁盘阵列、磁带柜、光盘柜的各种技术进行实现。该架构的特点是，连接到服务器的存储设备，将被操作系统视为直接连接的存储设备。尽管SAN的复杂度和价格已经下降，但目前在大型企业级存储方案以外还应用不甚广泛。

与SAN相比较，网络储存设备使用的是基于文档的通信协议，例如NFS或SMB/CIFS通信协议就被明确的定义为远程存储设备，计算机请求访问的是抽象文档的一段内容，而非对磁盘进行的块设备操作。

A storage area network (SAN) is a network which provides access to consolidated, block level data storage. SANs are primarily used to enhance storage devices, such as disk arrays, tape libraries, and optical jukeboxes, accessible to servers so that the devices appear to the operating system as locally attached devices. A SAN typically has its own network of storage devices that are generally not accessible through the local area network (LAN) by other devices. The cost and complexity of SANs dropped in the early 2000s to levels allowing wider adoption across both enterprise and small to medium-sized business environments.