分布式共享内存 (DSM), 也被视为一种分散的全域地址空间 (Distributed Global Address Space), 属于计算机科学 的一种机制,可以透过硬件或软件来实作。分布式共享内存主要使用在集群电脑中，集群电脑中的每一个网络结点(node)都有非共享的内存空间与共享的内存空间。该共享内存的位置空间(address space)在所有结点是一致的。简单说，同一时间下在结点A读取0x00001234会和结点B读取0x00001234得到一样的值。

In computer science, distributed shared memory (DSM) is a form of memory architecture where the (physically separate) memories can be addressed as one (logically shared) address space. Here, the term "shared" does not mean that there is a single centralized memory but "shared" essentially means that the address space is shared (same physical address on two processors refers to the same location in memory). Distributed global address space (DGAS), is a similar term for a wide class of software and hardware implementations, in which each node of a cluster has access to shared memory in addition to each node's non-shared private memory.